Re: PRS, A2, or...?
I have the PRS on a couple different ARs, including two 308 semi-autos. I like the PRS a lot and I recommend them. The stock has excellent adjustability, offers a great fit/feel, small butthook for weak-hand placement, rear rail for mounting a monopod if you desire, on and on...
On the downside...the PRS is a heavy mother and adding it to an AR-10 type rifle will only further increase weight on an already heavy rifle. I personally don't mind a little extra weight, but if you are planning on humping the rifle around the hills of Kentucky for hunting, you may want to go another route.
If you complete your profile to add the city/county you are located in...you may find a member here close to you that would let you take a look at a PRS equipped rifle. There are tons of members here from the Bluegrass State.