GI full size, purchased brand new. Won't go into battery most times (using ball ammo, for God's sake). Tried every mag known to man. Tried a stiffer spring. Shot 600 rounds thorugh it, in case it was "tight". Cleaned and lubed reguarly. Rounds just won't ramp into the chamber nicely. It's gotten worse, too. It's literaly almost every other round. Other satisfied customers notwithstanding, mine is a fucking piece of shit. I expect a brand new gun to go bang every time, without needing to whap the back of the slide. I've shot Lorcins that didn't fuck up this bad.
On a brighter note, I'm pretty damn good at failure drills - since it's not a drill.
Rather than dicking around with SA and mailing the gun off, I left it with a gunsmith. The sights on it SUUUUUUUUU-CK! I told him to install a set of Novaks, and do whatever he had to to get the damn thing to feed reliably. I'm confident that it'll be a fine weapon once the problems are fixed.
I gotta tell you though - leaving it with the smith while eyeballing a Glock behind the counter made for an interesting excersize in fiscal restraint.