The DPMS 308 and Armalite AR10T were great guns. While the DPMS was extremely accurate, it had the full bull barrel and was just heavy and akward anywhere but the bench. I do more than just bench shoot so I got rid of it.
The AR10T (T for target) was honestly the most accurate out of the box gun I've ever tried (shooting federal match 168's). It too was a little big and akward for running and gunning.
For me to keep a gun, it has to talk to me when I'm holding it(if that makes sense). Also being that I am a gunwhore, and having been in the retail gun biz nearly 20 years, I get to try lots of different things. I go through phases, as most gun nuts do and the big-semi's just phased out for me. Maybe I will go through that phase again, but I doubt it now that the AR15 platform has gone through such a renaissance as has never been seen before with any single firearm platform.
Seriously, the AR15 is like the mother loving Transformer of all firearms, you can convert/change it to nearly anything you want, and that includes calibers that can do nearly what the 308 will do. The AR15 is perfect for coyotes, prairie dogs, plinking,self defense and even close range big-game.
I do shoot a lot of big calibers, but mostly for big-game hunting. The AR 10/DPMS platform doesn't fit the bill for hunting big game in the west, where I hunt. It would do fine in a Texas box stand. So I choose bolt guns for most of my big game hunting.
So in a nutshell, while there's nothing wrong with it, the larger platform of the AR-10 just wasn't practical for me.