Actually the two savage rounds CAN be dandy Contender rounds as there factory ballistics ARE with in the T/C's limitations. Thing is both of these rounds are so frequieltly pushed to higher pressures they can quickly become a problem for the Contender frame. The 375 is loaded to some pretty hot pressures but with its .506 case head compaired to sub .473 for the Savages. Its a bit safer. It still can be a frame stretcher if pushed and lots of rounds are fired.
Simply the closed breech design of this gun store aching is a regular happenstance. This is the receiver is built to withstand a Serrano. Amount of it. This is kept in check by limiting pressures.
IMHO The 375 Win is one of the best woods range calibers. It has good diameter respectable bullet weight and at 50K+ darn respectable energy and velocity figures too. It surpasses the great 30-30, 35 rem as well as the old time 38/55 and newer 44 mags in these duties.
I have e two Marlins and altho my Contender barrels are long gone these Amrlins ain't going anywhere any time soon.

CW