I love Ron and his posts on AR-15. It's amazing to hear some of his reports about stuff and what parts break and what parts just aren't worth repairing.
His whole post about how Palmetto State Armory uppers working just as well as the high dollar ARs was pretty cool to hear.
I read this post not long after he put it up and it really made me realize I probably don't ever need a shotgun because the one shotgun he said will run forever the M4 I often hear reports on other forums about how it's not that reliable. At least on the Brian Enos forums the general consensus with any out of the box shotgun is that in order to get it to run you're going to have to send it off to someone that knows the gun well to get it to run and that is discouraging.
I believe GJM had the 14" Entry model, and if I'm not mistaken, the shorter gas guns can be more ammo sensitive.