Commander size with 8 rounds and a spare mag. Unless you are headed into battle that is more than sufficient-unless you really are clueless with a firearm.
AKA whatever works....
Normally, I carry a 1911 with 8 round mag. Feeling a little uneasy with all the bull**** going on right now, and with frequent trips through Atlanta...so I switched over to the M&P 9mm, 18 in the gun, 34 in back up...