Re: 22 semi auto??
The TacSol upper has a good reputation.
The common available dedicated milspec compatible are the TacSol, the Nordic, and the several Atchisson style ones (Spikes Tactical, Ciappa, CMMG.
All use the same mags.
I have no direct experience with TacSol or Nordic(it's newer).
I have five .22 dedicated uppers, three 16"(a M-4 and two CARs), a 20" NM, and a MK12 Mod O SPR. Great fun.All but the MK12 are Atchisson system bolts(Ciener, Spikes, CMMG, ArmaLite, TargetMaster, etc).
CMMG has a great dedicated upper for only $350 (Sierra? model).
These can upgraded for bolt hold open actuation and forward assist (not much need for my thinking). Great customer service, though rarely needed. I haven't one, but would have no hesitancy to spend my own money there.
You COULD get two 10/22s for a TacSol, but after you've finished fiddling, you'll have $2000-3500 worth of two 10/22s, and it still won't have AR ergonomics.
I've got seven 10/22s, too (3 shooter family).