imported post
IMHO: You have to start with a good belt & good holster.
Move it around on your belt (Good heavy,wide belt)
until you find what is your 'Sweet Spot'.
Put your pistol on and wear it around the house for a day
or two. You will get used to it. When you go out in
public, you won't be as self conscious if you are used
to the feel of the pistol either on your belt or in a
IWB holster.
Sometimes you will encounter a pistol wearing a man, and
not the other way around.
(Thats what we used to say about rookie cops)
After you carry for a while you get comfortable with it,
you relax and you 'Wear the Gun'.
A G-19 is not too big to carry. (Unless you are really small in statue) If you check on the Glock Forum, you will find that the G-19 is for many the weapon of choice.
The 357 Sig offers a little more punch than the 9mm or .45 but you pay for that extra punch with more felt recoil.
The price of ammo gives the edge to the 9mm (First) then to the .45 with the 357 Sig bringing up the rear due to $$$.