2 Doubles? Great!!

What Doubles depends on what/where your hunting.
I would agree that the 2nd Double be carried unloaded as one would have time to load and shot it for longer shots if such opportunities presented themselves.An unloaded QD scoped 375 Double combo'd with a 500NE would be great on a DG Safari.

If Ele were not on the menu and DG and PG was available a 470NE with a scoped 9.3x74R might work well.

For PG only a scoped 450/400 and scoped 8x57JRS might be FUN,FUN,FUN!!