http://www.survivalblog.com/2012/10/pats-product-review-rugers-1022-takedown-rifle-—review-by-pat-cascio.html Nice review on the 10/22 takedown. As you say, it sounds like it’s worth considering too. I like the idea of a rifle, even just a .22, that can be carried comfortably.
Check this out. You can get it in 9mm or 40 S&W and it uses readily available pistol magazines. It is very lightweight and folds easily to fit in a small 16" back pack.