Not to "poke the bear", but you kinda made my point. I own a GSR and I've done a number of things to it in order for it to meet my requirements, including a trip back to Exeter to fis a feed issue. Even the best can have problems. It doesn't mean the gun, nor the manufacturer is junk, nor that one should give up on the gun. My GSR is now my "go to" pistol and I wouldn't consider getting rid of it. I totally rely on it, but that took some effort.
Beyond that, you have complained that you had to adjust it down to 2.5. So? That doesn't imply a defect, nor anything at all wrong with the rifle.
Again, I want to stress that I am not bashing you. Its not personal, but I have noticed that Glock and Sig owners tend to have a bit unrealistic expecttions. The gas system is adjustible. That adds complexity to the operation. It takes effort on the users part to make it shoot correctly. The FAL is not for those who don't have the time/energy/attention span to learn the system.
I will also take a bit of responsibility here as well. I make an error in one of my posts to you. I gave a list of things that can be wrong with a rifle that requires a lower number on the gas setting. I should have also mentioned that 2.5 is quite normal. My list of things to look at is valid, but only if the gun suddenly starts giving problems on a gas setting that had previously been working well. Sorry about that. If you're not familiar with the FAL, you wouldn't have known this.