I've got about 700 rds through mine at this point and have had 3 FTF and 1 FTE. Other then that it has been a smooth reliable shooter. I also have a LWRC that I spent more on and can't really tell the difference. A buddy of mine has a Stag piston and it feels like a lower quality gun when compared to my Ruger or LWRC. I still prefer my Colts. Hope this helps, if you have specific Q's fire away and i'll try to answer.
I saw the Ruger at the 1500 this weekend, found it for 1450$. As I can see now, I will have to look around some for when I actually make the purchase. But I am considering making that rifle a major end item of my gun collection. I think it will be a nice, reliable piece of equipment.
I've been drouling over them since they came out also. You may want to do some reading over at ar15.com. When these first came out and guys were buying these and then immediately putting 1000's of rounds through them. Some of them were reporting some strange wear on the buffer tube, inside the upper receiever, and that the safety would go past the fire position.
These were old complaints from when the rifles first came out. From what I've read these problems have been slowly getting better as time has gone one. I really really like the idea of these rifles and think it's a heck of a package with a lot of extra's on it especially for the price range. I think $1350 is the max I would pay and that's about normal from what I've seen on gunbroker.com.
If you get one, I want to read all about how much you like it so don't be shy.
I handled one yesterday...boy was I impressed! I would like to put 1000+ rounds through one and see how well the piston system works after it gets a little gooy'd up! I like the adjustable factory butt-stock and the 4-way accessory rails all around. I loved the flip-up ghost sights. I would put a laser, light, night scope, and sling on it and be ready to go. If you could get it with a 16" barrel...that would make an excellent 'round the house' defense gun! The one I handled they were asking $1595 for it....so I handed it back! I'll probably wait until they hit $1250 or so...then jump on it.
Yeah, some were still having problems that AR15 piston conversions have... bolt carrier tilt. I think they have been remedied in the later rifles. I think they are slick looking, but so dang front heavy. Go for it!
When I got my M&P15T, I had both side by side comparison. I picked up the SR556, and noticed it is front heavy like the Sig 556 I had. Then I picked up the Smith&Wesson, I found it nicely balanced. So I picked the Smith instead.
I have one of the Rugers. Only been to the range with it once, but it seemed to shoot well once I sighted in the Troy flip-ups. Nice and smooth and didn't notice anything harsh from the new gas system. It does stay nice and clean. I now have it dressed out with a Magpul ACS stock (Ruger should have done that to begin with), Eotech sight, flashlight, KZ QD 2-point sling and KNS anti-walk hammer/trigger pins. Looking forward to more range time to see how well the Eotech works. I think Ruger did it really right with this one!