I bought a DPMS G2 Recon and want to replace the AAC 51T flash hider. Are their brakes gtg or should I look elsewhere? I've owned a Griffin Armament M4SD flash comp and loved it, so I may look at the 7.62 model. I do plan on buying a suppressor in the future, but for now I want something that will mitigate recoil and muzzle rise.

they work just fine

Aren't AAC brakes really expensive? The Miculek brake works great. There are some good YouTube videos out there comparing brakes of all sorts. Check them out.

Hmmm...I just noticed on Midway's site that the kind of AAC .308 brake I have is $140.  I got mine from CDNN last year for $80.  CDNN has them in and out of stock periodically.  I have that 51T ratchet model on a 16" Armalite .308 carbine with mid-length gas.  I installed that barrel to replace a 20" barrel.  I shot it with just the standard birdcage FH and then the brake to see the difference.  I didn't expect to notice much difference due to the fact that the AR10 is already a heavy rifle.  It was a noticeable difference on the positive side and so was the side blast.  I seldom shoot my .308's around other shooters, so that's not a big deal for me.  Also, I use some high end electronic ear muffs, and even shooting under a cover/roof isn't unpleasant.  Just using ear plugs on the other hand while shooting under a cover is not pleasant.  The choice of muzzle brake may also vary depending on whether you're going to use a suppressor.

They are very good at making it painful to shoot next to you.

They're very credible but no way I'd be excited about buying into 51t
Buy a suppressor then buy their brake

For muzzle brakes....

Here is a review of a ton of them. Most are not silencer mounts.

http://precisionrifleblog.com/2015/08/21/muzzle-brake-summary-of-field-test-results/

For that, pick a silencer first, then buy the brake you want. There are a bunch of great 7.62 silencer out there with decent brakes. At this point, I wouldn't buy an AAC 7.62 silencer if I were shopping. I'd more likely pick up a TBAC, Griffin, SiCo or similar.

I agree...that's why I mentioned it.  When I got that 51T, I had no intention of putting a suppressor on it.  If one isn't going with a suppressor then there's no need to worry about that aspect of it.  For $80 it was a good deal for a quality brake.  However, now that I have a Silencerco Hybrid in suppressor jail, I'll have to reconfigure all my muzzle devices that I want to run it on.  Oh the humanity!...LOL!

I picked up a SilencerCo Saker Trifecta Brake for $65. Now time to start the process of buying the can.

The Brakeout 2.0 is IMO the best muzzle device they make.  It's not loud at all, and very effective at killing flash AND recoil.