I have to agree with Old Glass, and would add, "the rifle that fits you best".

The cumulative effects of too many injuries over the years made me set aside my big bores, but I recently learned that I can still handle a decent medium if it fits me. My 9.3 is a good example.

It is built on a 98 action, which pretty-much covers the "reliability" criteria, and the mechanical aspects of the "familiarity" criteria. The fit is such that I can comfortably run 100 rounds through it in an afternoon's plinking, building familiarity. I've not found a .375 H&H that fits me as well, but a friend has a .404 that is a near-twin to my 9.3. I can put 50 rounds through it in an afternoon (probably more, but we only had 50 rounds with us that day). Either would suit me far better for hunting dangerous game than a bigger bore that I couldn't handle as well.