Budget! and competition specific.
10mm or 45 even at my measly @ 500-600rds per month vs 9mm
Are you getting to the range often? I'd guess there are some sweet outdor ranges near you or at least BLM.
I'm joking. 10mm is for FBI SWAT and agencies that might run into Polar Bears. Actually, I'm law enforcement for State Parks out here as well as a firearms instructor and TASER instructor and we shoot every quarter. ;)
I learned to shoot as a kid in ~89 with my IPSC shooter uncle, back when 10 was IN! Do most locals carry anything while hiking or mtb in that area? Plenty of lions and bears around that mountain..
Carrying inside the State Park or wilderness is prohibited by law. USFS would defer to state law, which is open carry of an unloaded firearm only. If I'm off, I carry a SpiderCo; more worried about some tweaker than bears or Mtn Lions.
Locals seem to carry BFK's (Big f'ing Kinves) mostly.