I'm shocked that this forum seems to only talk about Nightforce. I had an ATACR F1 and was so unimpressed I sent it back.
I agree with
@Rudolph Ferdinand that you should look at Precision Rifle Blog's huge comparison of high end scopes. His amazing analysis led me to believe that if you couldn't afford a Schmidt and Bender, the best scope would be US Optics. For no other reason than it got a perfect score on tracking (something Nightforce did not, nor very many other scopes did).
I got one and can't speak highly enough about my scope. Do you realize US Optics may be the most customizable scopes there are? They have since limited what they customize, but still offer an impressive amount of reticles, for example, including Horus. They are also amazing to US military members. I was given 20% off and a free Cerekote coating in burnt bronze (and not to sound too much like a Homer, but I honestly love the T-shirt they included). Their customer support is amazing and I felt like they were my friends (I didn't know a thing about them or the company before my order).
I routinely use my scope on a POF AR-10 with 20" barrel. Even with the detachable quick release mount I can hardly believe how accurate it is. For example, at confirmed 610 yrds (via GPS) the kick of one of my shots knocked my 8"x3/8" swinging plate on top of 2x4 stand I was using. I was hitting so true, it took only my second shot to shoot the 3/8" horizontal plate off the stand, which is exactly what I was aiming for (And a coworker witnessed it and the skimmed bullet mark on the top of the 2x4 I still have shows where it hit. And this is shooting a 308 people! (using Hornady AMAX Superformance). I also was hitting 1000 yrds almost looking right into a setting sun, thanks to my US Optics scope. I didn't have the sun visor, but the glint on the bullet was so easy to see I actually walked my rounds onto the target .. at 1000yrds with my .308!
I just happened to win an NRA Whittington Center sweepstakes and got to select a package of 6 guns... I'm selling the 338 Lapua mag, but I'm going to keep the Winchester Model 70 in 300 Win Mag that should be coming in another three months (I'm told). And I bet you can guess what scope I'm going to mount on top of it.
(As a side note, I analyzed 30 different types of manufacturer's ammo through my rifle and I found that Hornady Superformance AMAX was best overall for accuracy and standard deviation of fps).
(Update: oh, and a couple years later, I called up US Optics because the illumination in the scope was no longer working and new batteries weren't fixing the problem. They said they had upgraded to a new button and battery attachment (which was compatible with my scope) and they sent me a new one for free! So customer service is first rate in my experience).
