I could hardly find time to do 3d nowadays. When I do find some, I'd just watch Andrew Brown's Wristwatch tutorial. Which means everything else is in the backburner, ie, C6, Blender (which I had planned to study further before modo and C6 came, especially after having bought a book called Essential Blender from BF before that.) I had to choose which one to spend my little time in. I picked modo301, which happened to work smoothly on my old pc.
Andrew Brown's Wristwatch video is an excellent tutorial to get to know modo. I highly recommend it. I recently preordered Dan Ablan's 301 Signature Courseware. (The price will be more than double after its release date.) The difficult part for me is the choice of project where I could apply such newfound knowledge.
Poly/subd principles are universal. Of course, you can use whatever modeling app you're comfortable in to come up with the same model. The tools are the same, it's the workflow that varies.
About Rhino, is this something like Amapi's DG, shorty?