I'll second 3dc... Bodypaint is good of course, but it's overkill for most texturing. In my experience, a 3d painter is mainly useful for stuff like fixing seams and in cases where the UV map is a mess. Can also work nicely for creating wholly original textures by hand. All this you can do in 3dc without spending a bundle on bodypaint.

For everything else, nothing beats photoshop. It can handle far heavier files (and texture files can easily get to 700-800 MB) has all kinds of neat editing tools that you wont find in any 3d painter and is very fast to work with. It should be your main workhorse.