Here is their patent on a 33 round .22 LR magazine that can fit in the grip of a pistol. Rimmed cartridges can work in large capacity magazines, but they need to be designed right.
The patent concept seems sound.
http://gunwatch.blogspot.com/2015/01/kel-tec-has-new-patent-for-33-round.html
Seems like making an autoloader anything in .22 magnum has some challenges associated with it that I don't really understand. I've heard about case head separation, etc. Has Savage found a solution to these problems, at least in a carbine/rifle in the A22? (Rhetorical question; time will tell.)
My problem is I don't necessarily have the budget to do my own field testing...
OTOH Ruger already makes the SR-22 with a threaded barrel, etc.
10 rounds of .22lr, or 30 rounds of .22wmr, but some question the reliability, is it worth the difference? Life is full of trade-offs and none more apparent than in one's choice of weapons, especially handguns.