Already own the Ruger American with rotary mag. VERY nice, compact little carbine that makes a lot of sense in a "post-prepper" sort of way...once somewhat wakes up and realizes getting into "firefights" in a post-SHTF survival world is a quick way to no longer need air.
There is nothing at all new about detachable box bolt guns...I think the British pretty much set the concept with the Lee-Enfield, and who doesn't remember the FN 30-11 with detachable box.
Having a larger magazine capacity that can be rapidly replaced on a bolt action is a great idea, long vetted.
I love everything about the Ruger American EXCEPT the cheesy, plastic, somewhat flimsy, rotary magazine. The only thing the rifle needed to make it superb as a "Scout-sniper" rifle is a sturdy, durable, robust, reliable magazine such as the Magpul AR design.
I just ordered a .223 AR magazine version and was glad to pay the extra money for a turn-key, compact, highly portable, light-weight, simple and reliable rifle.