Yeah, its always swings and roundabouts.

Firstly the problem is, people like mudbox because its like maya and everyone is shit scared of the Zbrush interface because it isnt - period. Zbrush just thinks a little different but fact is its all there in front of you, just look and you will find. Texture wise, mudbox is very good where as Zbrush still falls over at importing 32bit textures -export is fine, but I will say Pixologic have vastly improved the texturing too with the introduction of spotlight. Zbrush's sculpting tools will wipe the floor with Mudbox -thats a pretty much known fact -displacement map extraction is better as is Normal Map generating in Zbrush, though earlier versions with codes was an absolute ass. Mudbox however has a thing called Vector Displacement maps, a cross between normal and dis maps - they look impressive but I have yet to use them.

at the end of the day its horses for courses and what works best for you as an artist

And oh yeah I nearly forgot....Zbrush's new dynamesh -hahahahahaha Amazingly fast and furious, pull your mesh out in strands and reattach to the mesh into a single click....jeeez I love it

Jay