I've got one and I can honestly say after waiting 8 months for it, I almost turned right around and sold it. It's growing one me, but I don't think I'll keep it for ever.
The functioning does get smoother after a few hundred rounds. The last couple of times I've been to the range with mine it hasn't malfed, but it certainly did a few times too many while breaking in. Granted I was breaking it in with some surplus junk and not doing much other than polishing the bore.
The heavy barrel, which I have also, is probably the least worthwhile option I can think of. The accuracy isn't any better than the light barrel from everything I've heard and even if it is, I wouldn't describe it as accurate. Combat accurate maybe, but even that's a stretch. The heavy barrel does add too much weight exactly where it's not needed. I would venture to say the only reason to get one is if you plan to cut it back to 11 or 12 inches and want a shoulder for your flash hider. (Which was my plan since I intended to keep it at least until I leave California.)
As for the safety, I had the same issue. I think it may have something to do with the Ergo grip, which I'm also running, although mine is probably ten years old. I bought it for an AR and then tossed into one of my boxes of random gun stuff and forgot about it. Anyway, I ended up drilling the hole in the grip for the safety spring a hair deeper and then fine tuning it by slowly shortening the spring. Works flawlessly now and with the kind of pressure you would expect. (Which is to say you don't have to get completely out of position to make it work.)
Honestly, the fit and finish as well as some of the design work leaves a bit to be desired. The only thing nice about the stock is the folding mechanism. Since I've got a fixed, California version, I would say the stock is functional at best. And what were they thinking when they stuck that sling loop on the top of the stock? I think I'm gonna go cut that thing off before it bites me behind the ear one more time.