I haven't seen an example of this rifle yet. I remark at this time because the rifle reflects an industry trend toward the closed top, and because it is quite a departure for Ruger. Their high powered bolt actions have heretofore been based on the Mauser 98, a conservative approach.
The Model 77 series (son of Mauser) continues in production, including the nifty Gunsite Scout Rifle.
Some previous designs that followed the closed top, interchangeable magazine approach are the Steyr SBS and the Tikka T3. These are successful and well liked rifles. Perhaps Ruger called their new model the American to fend off the observation that it owes a certain amount of its design thinking to Europe.
No word yet on the price of spare magazines for the new Ruger American.