My suggestion on a CCW weapon is smaller is better. Find a weapon that you are comfortable with that is EASY to conceal and that you will not mind carrying EVERYWHERE with you. If the weapon is too big you will pick and choose when to carry and then you might as well leave it at home because the bad guy will strike the time you deceide not to carry anyway.

Also pick a weapon that you can manipulate without much thought, I love the Glock for that reason. You point the weapon and pull the trigger, you do not need to mess with the safety as it is built into the trigger.