All have their problems, Remington and Marlin most mentioned. Remington ammo also takes lot of hits recently. I've bought two Remington M-870 shotguns, a 12 ga. and a 20. Both had feeding issues, and both were the higher grade Wingmaster guns, not the cheaper made Express examples.
I'm on one Ruger board and read the other, so see complaints about Ruger, too. Most common are probably canted revolver barrels. Add some cosmetic issues, some of which can be fixed on stainless guns with some metal polish and elbow grease.
BUT...everyone posting seems to agree that Ruger offers outstanding customer service and will fix any flaws and often do more than was expected for the price. And they sell enormous quantities of guns. The good ones seldom elicit comment. Only the bad ones get mentioned. Those I've examined or own are all extremely well made and fitted, certainly as well or better made than S&W's. For reasons that we are no longer allowed to discuss on this board, I'd buy a new Ruger over a new S&W. Not everyone agrees; certainly not everyone on THIS board!
Beretta has very high standards, but the Beretta board has shown a few M-92's with canted front sights, and the company was reportedly not cooperative in helping those buyers. Said that they should have paid more attention when buying, according to posters. I've probably bought my last Beretta after reading about their customer service. Their small Tomcat .32 seems to have had many problems, inc. frame cracking. I think the gun was too small and/or lacks the proper metallurgy for the .32 ACP round. That's personal opinion, based on reading a lot of complaints about that gun.
In fairness to Beretta, I should note that those slightly bent M-92FS front sights could easily have resulted from some clumsy retail clerk or prospective customer dropping the guns long after they left Beretta. I know of some stores that have the clerks put away guns in a secure area every night, and those minimum wage clerks often don't care if they scratch or otherwise damage a gun. I was in one store where customers can handle long guns without supervision and almost all I looked at had cosmetic issues. It was appalling!
I want to add that my own M-92FS is very well made and functions flawlessly and when I bought a M-391 Urika 20 ga. shotgun in the Beretta Gallery a few years ago, the staff gave outstanding service and were very patient as I decided between a few different guns.
From what I can tell, USRAC (Winchester) probably makes the best quality US-produced hunting rifles, and Sako (Finland) also has a very high quality level, as does CZ (Czech Republic) , although they have some rough finishing issues, like rifle bolts that often need smoothing with use and perhaps some polishing compound. But they are otherwise quite something, although prices are rising. I think they're improving in the action smoothness regard, too.
No brand is immune from problems, as I'm sure that even Mercedes, BMW, and Lexus have car problems. Companies are made up of humans, and some have more personnel problems than do others. Colt had awful labor union problems for years and may still, for all I know. But their guns that I've seen lately are better than in the 1980's. One of my pet peeves has been that on most postwar Colt Government Models, one can look between the slide and frame at the front and usually see the recoil spring, as on late war guns made in some Nazi-occupied countries. I have seen that rarely in the last few years, although I haven't handled a lot of Colts. Sight channels have sometimes been cut in slides at an angle. Watch for canted sights, front and rear.
Board policy here now prohibits discussing S&W issues, so I can't.
But I'll say this: whichever brand you buy, you'd better see and handle it in person first and look it over with great diligence. It's a lot easier to avoid buying a questionable gun in the first place than to have to return it later for repair.
Store lighting sometimes makes it hard to see small flaws.
Be alert!
That also applies to knives and to such diverse items as bath towels and plastic water pitchers. The way that quality control is now, especially with many items made in Third World countries, the buyer needs to be very wary. How' s that look in Latin? Caveat magna emptor?