I have a 94BB in 375 and a Marlin in 35 Rem. The platforms are different - they have a different weight and feel to them. There are other differences too. The Winchester has a faster twist (1 in 12”), deeper rifling and a large throat (by levergun standards) whereas the Marlin has a slower twist (1in16”), microgroove rifling (shallow) and no throat.

With a 375 these days you really need to be a bullet caster to extract the best out of it. It easily handles 300gr cast pills at 1850 FPS. Hornady dropped their 220gr FN bullet for this caliber, which was a useful bullet. Cases are now available from Starline but you can easily form them from 30/30 brass.

Microgroove rifling is no impediment to getting cast bullets to work. In my 35 Rem due to the slower twist the best I have managed is a 247gr cast pill (Saeco 352) at 2000fps. Accuracy is brilliant.

The throat of the Winchester is designed to dissipate pressure quickly. It’s somewhat like a 458WM throat.

The other point of difference is that 35 Rem factory ammo pressure is held to a low level - around 33K. Back in the pre WWII period Remington marketed faster ammo but some rare models (not Remington) were having problems. Boosting pressure to 40K (same as a 30/30), which is safe in a Marlin, will yield another 200FPS.

IMO the two cartridges can be handloaded to broadly similar performance levels.