Here's my quickie Campfire version: Have not been able to see any difference between the .300 with 200 Partitions and .338 with 210s--except 200s from the .300 penetrate noticeably deeper. In general, yes, the .375 (or similar rounds, such as a 9.3x62 loaded to modern pressures) does have an edge. But a lot depends on where you hit them, and many hunters don't differentiate between "bone" shots and rib heart-lung shots.
For the longer version, you might want to read my chapter on killing power in Gun Gack II.
