The Rosens are the most beautiful but are very pricey. Plus, they're a pain to break in.
Lou Alessi's holsters are top quality. In addition, Lou's a great guy to deal with.
Rusty Sherrick's holsters are made out of strictly horsehide. They last forever and are very functional. Rusty lives about 10-15 minutes from me and is a heck of a nice guy.
I'm using an IWB from AKJ Concealco. I like his design in that I can adjust the rake (or cant) of the holster to fit MY carry style. One thing I have noticed with the Ultra CDP though, that bead blasted finish on the slide picks up leather on its way in and out (wipes right off - but the first time you pull it out it looks strange). I figure a few more months of carry will smooth the inside of the holster enough that this should stop.