You can actually paint texture maps in z-brush, and export them to photoshop, and then export to maya. Bad thing about Z-brush is that it sucks at making uv maps. You have to have a 3rd party plugin to make a usable uv map in z-brush. Other wise, your texture map is gonna look like somebody threw a puzzle on the ground and ran it over with a dump truck ( not my quote but btw ). I think Z-brush version 4 has a plugin called UV master that does a pretty good job.