this will be my first holster purchase.
Trust me... it won't be your last.
Everyone starts out with what they think will work... based on any variety of information sources. Then, after you try something for awhile and understand the realities of wearing a handgun all day, every day... you'll start to search out more specific "holster objectives", based on you and your individual needs.
Figure in the cost of a good gun belt. Dress, casual or whatever in-between... you'll need a real gun belt to support the holster properly, even if it's a paddle rig.