I have 5 Glocks and I would say if you have a 26,go with the 19.
I have a 19.17,23,27,35,and 30 - just realized that makes 6,LOL at me.
I really like the 9 MM for the fast recovery second shot,and with good modern ammo you are not giving up anything.
ESPECIALLY since shot placement is the only thing that matters.