This is an alien bust I'm currently working on. It is based off of a design for my character Kaiden's creature form. It still has a way to go but at least it is started.
The base was modeled in maya and the details are being done in Z-brush.
It really depends on how comfortable you are with z-brush. You can build a functional model from the ground up strictly in z-brush if you wanted. I don't like re-topologizing in the program so I tend to use maya more often than not to build most of it.
This is how far I took this model in maya before moving it over. sorry I don't have a screen cap with the wire frame. I don't have maya at home to get it easily.
http://s9.postimage.org/6e73k2l7x/396026\_4331198482404\_697101750\_n.jpg
http://s11.postimage.org/hbvci8rch/376258\_4331198282399\_730917282\_n.jpg
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CrazyDragon
Sadly, my final year in my program and JUST NOW we are learning about mudbox (but I want to work in Z-Brush, seems to be industry standard). So I was wondering, how far do you model in Maya before you know you've done enough work to move it into Z-Brush?