Let's be honest: this is going to be a controversial category. For one thing, there are lots of great frames out there, so I'm going to offend somebody by leaving out their favorite. But the whole point of this page is to help you narrow down your options, so I've picked just a few that I think are great.
The second thing that will make this category controversial is the inclusion of both a $25 Chinese clone frame and the $100+ original. Some people are going to be offended that I even mention the clone. Others are going to be insulted at the inclusion of the "overpriced" original.
In my opinion, the cheap "clone" frames on this page are good value for money, but they're not as good as the originals. The quality of the carbon used and the machining on the cheap frames is consistently inferior to that used on more expensive ones. But if you're on a tight budget, a $25 clone will get the job done. Some people might not even be able to tell the difference after a few crashes.
The "overpriced" original frames are generally higher quality than the cheap copies. Also, you can't ignore the cost of development and customer support. Once a designer comes up with an original idea, it doesn't cost anybody else anything to copy it. Designers who truly come up with innovative ideas deserve to be compensated for it, and paying a premium for their frames is how that happens. Buying from a vendor like GetFPV means you can count on actually getting somebody on the line if or when you have problems, but somebody has to pay the people who answer the phones. And those people are getting American wages, not Chinese wages.
If you care about all of that, you can buy a higher-priced frame with a smile.
And if you don't care about that and just want the cheapest frame you can get that isn't a piece of junk, I won't hold it against you (but frame designers definitely will).
Freestyle is like dance. The goal is to move the quad through the environment in interesting, exciting, and beautiful ways. A freestyle quad may have power, but raw speed is not its end goal. Freestyle frames are usually larger and heavier than frames focused on racing. They're simpler to build, since the pilot isn't focused on shaving every single gram of weight that they can. Freestyle frames are always designed to carry a High-Definition camera such as a GoPro.
If this is your first build, you should definitely buy one of the "freestyle" frames on this page. A "racing" frame is probably too challenging for a novice because the electronics will be harder to install.
cheapest WORTH HAVING
The ImpulseRC Alien may be the single most successful mini-quad frame ever. The Martian is a pretty solid copy of the Alien, at less than 1/4 the price. The Martian is larger and heavier than the most cutting-edge frames available today, but this makes it easier for a novice builder to fit all the parts into it, and the difference in handling will hardly be noticeable.
Consider ordering some spare arms, top plate, and bottom plate, when you order this frame. You'll probably break one eventually, and you won't want to wait for the slow boat from China to get back in the air.
The Reverb is the sequel to the ImpulseRC Alien, possibly the most successful mini quad frame ever. The Reverb keeps everything that made the Alien so successful, while adding modern design touches like reduced weight, lower top deck for tighter center of gravity, and smaller wheelbase for better agility.
There's a reason that the original Alien stuck around as long as it did: it's easy to build, durable, easy to maintain, and flies amazing. With the Reverb, ImpulseRC has brought the Alien's success into the modern era.
In terms of popularity and innovation, the Chameleon may be the only legitimate contender to the Alien's throne. It has an innovative aluminum front end that protects the FPV camera and provides a mount for the HD camera with integrated uptilt adjustment. No need for a 3D-printed GoPro mount on this frame! The Chameleon has a low-deck design that centralizes weight, making the quad more nimble. The low deck makes it more of an intermediate build, since there is less room to fit all the equipment in the frame.
If you're at all interested in the Chameleon, you must watch this video review, by Soma, the developer of the Alien. This may be the best frame review I've ever seen.
Mini quads are expensive. One way to save money is to buy clone products, like the Martian above, which is a blatant rip-off of the original ImpulseRC Alien. I never judge people for how they decide to spend their money, but I do encourage you to support original creators if you can.
The Strix Screech is proof that you can support original creators and still get quality products at a decent price. It's designed by ReadyMadeRC, a stalwart of the U.S. RC hobby industry. It's a great freestyle frame (although you could race it if you really wanted to). And it's under $40.
The goal of a racer is to go fast and finish first. Racing frames are built as light and aerodynamic (thin) as possible. They're also more compact and difficult to build.
Durability is a challenge for racing frames. If the racer crashes out, he's not going to win the race. But additional strength usually equates to additional weight. The best racing frames strike a fine balance between these considerations.
One defining characteristic of today's racing frames is the Stretched-X motor layout. These frames have the motors farther apart front-to-back than side-to-side. It's hard to tell whether this offers any legitimate benefit, or whether it's just another fashion trend. Enough top racers are flying Stretched-X that maybe there's something to it.
Racing frames are more likely to use an under-slung battery. They can usually carry a GoPro if need be, but may be designed with the GoPro as an afterthought, rather than a necessity.
All of the "racing" frames on this page are intermediate to advanced builds. If you're a beginner, you should buy one of the "freestyle" frames above and enjoy racing it. You won't be as competitive as someone with a purpose-built racer, but you'll still have a great time.
CHEAPEST WORTH HAVING
OWLRC DRAGON DSX-5
The OwlRC Dragon was brought to me by its designer, Grisha Lutsenko, for help in bringing it to market. Something about it really struck my fancy. The four arms come together to form a solid plate, so you get many of the best characteristics of a single-piece bottom plate, while still being able to change an arm if you break one. But you probably won't break one! The quality of the carbon used on this frame is top-notch. It's one of the stiffest frames I've ever seen, too. The main body is compact enough that the quad handles great, but roomy enough that you won't struggle to fit everything into it. To be honest, I'm not even sure how it's possible to sell it for the low price they do, but I'm not complaining!
Light. Fast. Simple.
RDQ Mach 1 Stretch X
The Mach 1 is one of five frames selected for MultiGP's prestigious Spec-Class racing league. Frames like the Mach 1 reduce weight by minimizing the amount of carbon in the frame. The "frame" consists of little more than a base-plate and a top plate. Fitting all of your electronics in this frame will require a lot of thinking ahead. Some components simply won't fit, so you might want to look up somebody else's parts list before proceeding. But you'll be rewarded with an incredibly nimble and fast quad. The centralized weight will make it turn on a dime, and the small surface area minimizes drag.
Metal + carbon = awesome.
GEPRC Leopard LX5
This unusual quadcopter combines a 7075 aluminum roll cage with the usual 3K carbon fiber twill base plate. The result is a quad that's incredibly crash-proof. The metal roll cage provides maximum protection to the FPV camera, which many other frames simply leave hanging off the front of the frame, almost as an afterthought.
The arms of this frame use a "true-X" layout, where motors are arranged in a square. This means that the quad can be expected to have consistent and neutral handling on the pitch and roll axis. The arms are removable so they can be swapped individually if they break.
The listing has three different sizes. For 5" props, you'll buy the 220mm version.
every detail is right
The attention to detail in this frame puts it in a league of its own. Notice the engraved sections which reduce weight without compromising strength. The camera pod protects the camera from the impacts that are inevitable in racing, while holding the uptilt angle securely. The carbon fiber is laid in multiple directions which maximizes stiffness and strength.
The QQ190 puts the camera on top of the Flight Controller stack, rather than out front. This equalizes weight distribution on the pitch and roll axis, resulting in unparalleled neutral handling.
The link above is to the 3mm version of the QQ190. If you plan to crash extra hard, go for the heavier, but stronger, 4mm version.
Purebred Racing Machine
Superlight 5" Norris
Catalyst Machineworks pioneered this style of frame, with full-sized arms but a smaller chassis. This keeps weight centralized for nimble handling, while giving just a little bit more breathing room for build and maintenance compared to ultra-compact frames like the Reaper.
With the right components, this entire quadcopter can come in under 200 grams. It's ridiculously strong, light, and fast. But you have to be careful in your parts selection. If you build this frame too heavy, it won't be durable at all. Check out Catalyst Machineworks product page for a list of suggested parts.