Wow, that Galco looks BIG :shock:. It could just be me, but the example pics, and that thumb strap, make the gun seem gargantuan. . . which isn't necessarily a bad thing.
I'm all for supporting custom makers, especially locals, but you don't always have to.
I use an Aker bodyguard with my 4' GP. It's surprisingly stout and flat for a production holster, the thumb strap is small (goes over the rear sight area opposed to behind the hammer), and it feels right, but it doesn't have the retention the Galco does.
Aker makes some good stuff, and if you want to bargain hunt, search for "Rod's Resale" via Ebay.
P.S. Just looking around, it seems Aker stuff can be harder to find, ditto revolver gear, but worth the look IMO. I'l letcha know if I run across anything!