I have 2; 13.7 Infidel and 12.5 Crusader, and I love them. Not playing the brand whore card, as I have many different brand uppers, and like them all for different reasons.
My Noveske uppers are older models, so I cannot speak to today's quality or spec, but they are gassed as close to perfect as they can be for the ammo that I use. Even with my suppressor mounted, that Crusader barrel has not needed the gas cut back. I can spin the can off, and it shoots softly, and ejects reliably, every time.
The Infidel is midlength gas, and many doubt its reliability based solely on the fact that is has too short of a barrel for the gas system. It has never missed a beat, even with lower power ammo.
The accuracy with good ammo definitely beats all of my other rifles. I just need better glass so I can get out there farther, and enjoy what they are capable of.