I have found that good customer service by firearms manufacturers is the rule rather than the exception. I returned a Remington 700 because there were some machining marks near the muzzle in the rifling. They sent me a new rifle. I had an OLD Remington primer fail and cut my bolt face. I sent them a letter with the info and a picture. I received money for a new bolt and 1000 primers. The only two that I was unsatisfied with were Ruger and CMMG. I sent a Ruger rifle back because it didn't group to my standard i.e. not as well as other Rugers I owned. They shot it and sent it back saying it met there standards. I sold it at the next gun show. CMMG built an AR upper for me. It required 14 MOA left windage to zero. I sent it bach and described the issue. when it returned, it still required 12 MOA left windage. Disappointing. Amazingly, of the over 100 firearms that I have owned in the last 40 years, those are pretty much all of the problems I have experienced.
My vote for the all time best customer service in the firearms world is for the CMP. They will make things right. Case in point: Last year I purchased a very nice M1 that I was gong to use for JCG matches. It hit a bit (several MOA) to the left, but I assumed it was an improperly indexed barrel. I sent the rifle to my gunsmith to have it "tuned" and a trigger job. He informed me that the barrel was bent. I sent it to the CMP and received a call from their chief gunsmith. He said they were going to replace the rifle with one that was equally new (this thing was beautiful) and then he asked me if I wanted one from a particularly collectible serial number range. Of course I accepted. He finally, said that the trigger in my returned rifle was really good (it had been tuned by the smith) and wanted to know if I wanted him to swap it out with the one on the new rifle. The replacement rifle was every bit as beautiful and tight and new as the returned one. I have returned several rifles to CMP that has issues. They have always made things more than right. I always received a replacement that was better than what I returned.