My problems with Palmetto State Armory:
1) I ordered two spare bolts. One bolt had a machining burr on a lug. I contacted them, they shipped me a replacement and a call tag, all was good.
2) I bought a complete upper in a 20" rifle setup. They assembled it with a round handguard retainer cap instead of triangular. This is acceptable but kinda weird. Not a big deal, and I didn't bother to contact them about it. From reading forums I wasn't the only one to get this and think it was weird.
3) From the same order as the bolts, I had also ordered a complete BCG. When I went to use it almost six months after buying it, I had function problems with the rifle. I discovered that the carrier had a poorly machined cam pin track, out of spec compared to all my other carriers. Switched to a DD BCG and the rifle worked perfectly from that day onward. I contacted PSA; this time they said I could ship it back on my dime for a replacement. I did, and instead of a replacement they "worked on" my defective BCG and sent it back to me looking heavily used, and with something jacked up so it was no longer possible to disassemble because the cam pin would not come out. I contacted them again, got promises of a replacement but then nothing happened for a month despite repeated attempts to contact. Finally I posted about the issue in another forum, and a few days later a PSA rep contacted me and I did finally get a replacement with a call tag for the defective one, but no reimbursement of my shipping costs for its first round trip back to them.
You can chalk it up to growing pains or whatever. I don't think they're bad, but I think there has been some ridiculous fawning over them in the last year as being the greatest new thing. They're just another company trying to get market share by offering low prices on stuff that claims high specs. I think they have had some QC and customer service issues.