I was in a rut carrying the same guns and using the same holsters. I confess my favorites have changed over the years. I will usually get a new gun followed closely by a new holster (or two) for it because I want to carry it.
The result is a drawer full of holsters.
In the Winter the shoulder holsters come out. Winter coats allow me to carry using ANY holster in my collection. Today while I was out and about I was wearing one of my cheaper shoulder rigs. I think I bought this one from CheaperThanDirt.com after seeing a friends at the range. I think it was only $30 but it works great with my Beretta Px4 and two mags.
I have an nice vertical Bianchi shoulder rig for my Smith &Wesson .44mag. It's the best holster for it because it weighs a metric ton.
I have another vertical rig from Uncle Mike I got specifically to hold my Beretta 96D with the suppressor attached.
In all I must say I like the vertical configuration best. The horizontal rigs end up pointing at the guy in line at the store behind you. While safe, I still like the vertical rigs better. They are great in the car. Best of all, they help keep my pants up in stead of trying to pull them down!
--How many Holsters do you have?