JJHack, who used to post here, and has far more experience with deading animals than I, stated that he thought the 165 is just about ideal in the 06, Won't/Can't argue with that - but I still like the 180.
When I started Big Game Hunting with a .30-06 I was told that 165 gr. are the best rounds for a .30-06.
Like you, I went straight for the 180 gr, more oomph for the same money lol
My .30-06 loves them 180 gr., shoots them like a laser beam and whatever they hit is DOA.