I've had a Ruger MkIII 22/45 for a little over a year. It's the slab sided barrel with the grips molded in the frame. It was the least expensive model and I think it's been discontinued.
I have no idea how many rounds I've put through it but I wouldn't be surprised if it was well over 2000 rounds. With only one dud. I know it was a dud because it wouldn't even fire in my 22 revolver.
I've not exactly been picky about ammo for it either. I think I've put every bargain brand of 22 through it that I would find at WalMart or Academy, whatever was on sale. I have never put any CCI or any premium ammo through it. Not that some of that is necessarily that expensive but why spend more when you can pick up a pack of 50 rounds for $2 or less. I am not shooting competitively but for complete fun. Which is what the 22 delivers!!
I have ZERO complaints about my Ruger or bulk ammo for that matter. I am a big fan of the 22/45. (And my SR9c...but that's another thread!) Frankly, field stripping and cleaning are pretty easy once you get the hang of it. It's just not that big a deal.
I do clean it after every shooting session. Maybe that's why I don't have any problems!