Even when I was a kid I don't remember 22lr ever being reliable. We always had perfectly good rim strikes that wouldn't fire a round or perfectly fine hit that would result in a small case split and powder getting blasted into the action (or the face with my 22/20g over under). There's got to be high quality stuff somewhere...
As for mouse gun...I have a keltec p3at that's just too picky with ammo.
I don't like to carry it as it hurts to fire it. I'm seriously considering just carrying pepper spray as a secondary instead of a BUG, having something less than lethal seems like it might be a wise option.
CCI Mini Mags and CCI Standard Velocity
The match grade stuff is generally quite reliable too. Wolf Match Target and Match Extra, SK match stuff, probably anything Lapua or Eley. Provided the standard velocity recoil impulse is enough for the firearm to not have any issues from lack of oomph