This subject comes around seems like every month or so. Your carry gun is a very personal choice, no one can make that choice for you.
I have been carrying a gun professionally for over 3 decades and concealed that long as well. I have also gone thru revolvers, and auto's of every shape and size.
My experience has shown me that I will carry the biggest, most powerful gun I can conceal and shoot well. I am a huge fan of the 357 Magnum, it just works. My carry gun these days in my Glock 27/33 which is a 40 Glock converted to 357 Sig. It holds (with the G23 mag I carry) 14 rounds of 125 grain Gold Dot @1450 FPS.
http://www.underwoodammo.com/357sig1...ntboxof50.aspx.
Add 1 reload to the mix and I have 27 rounds in the same size and weight package as my 640 and 15 rounds assuming I would carry 2 reloads.
If you want a revolver, carry a revolver. Whatever you carry, master it so that you can run it without conscious thought. If you have misgivings about safely handling your gun, you need more training.