The one on the far right is a bushmaster with a mini Y-compensator permanently pinned unfortunately, but it is a good compensator.
It also has:
Magpul CTR, MIAD grip, MOE hand guard and BAD lever I had a KA quad rail originally but took it off to cut down on front end weight.
AZ GG&G Cantilever Aimpoint mount, rear sight and dual single point sling footman's loop.
Aimpoint Comp M2
Surefire flashlight with some random mount (not sure of the brand)
Since I am physically addicted to stippling my hand guard pistol grip and all of my PMags are stippled.
The middle AR is just a basic DPMS I traded for a Glock 23 and 400 rounds a few years back before the price jumped and I have just recently started to upgrade, the only thing out of the ordinary is foiliage green dura coat on the M2 and a MI 10" specter length free float hand guard.
I have been using them at work for about 5 years and beat the hell out of them and they have held up well with the exception of the brightness knob falling off every now and then on the older models. I also like having the ability to fire out to 300 meters, with the EOTec it tends to get a bit blurry past 150 meters and I have seen quite a few of them break. I had an ACOG for a while but couldn't justify leaving it permanently mounted on a carbine length rifle, a 1 power scope is all I need on it in my opinion. I am not trying to talk trash on other optics that has just been by personal observation.