The Marlin Papoose is a better choice of the "spare" .22 if you are a survivalist, because it is a takedown,with both sights on the barrel (unlike the pos AR7) It also isn't made by that traitor, Ruger. If you want to learn to use the AR swiftly, the 10-22 does not handle like the AR, lacks the same sights, trigger, safety, etc. If you are going to shoot 50,000 rds in 10 years or less, I recommend that you get TWO conversions (eventually) and a dedicated .22 upper receiver, to keep the wear and tear off of the "carry" .22 unit, and to allow the sort of precision that many want in a small game rifle. The unit usually groups 1" or so at 25m, and its POI is usually within 1" of the 223's at that range, but some units are problematical, both for group size and POI, and they might need considerable smithing. Who says that you will be ABLE to go get that other gun?