The default Rhino renderings are horrid, you’ll have to use a plug-in to get good-great renderings off Rhino. If you know the basics of Rhino (the 3d modeling part) and just want better renderings, download any/all of the plug-in trials listed on the site below:
Agreed, also while it’s not a traditional renderer, check out Auxpecker.blogspot.com, it can yield pretty cool studio environment lighting type shots and allows you to view realtime the same as shaded view mode. Before Hypershot came out, I really thought Auxpecker was THE solution for quick realtime type visualization. It has it’s limitations (no real reflections) but it is pretty awesome for what it is. Pretty sure it’s still free too! I would also definitely give hypershot a try, it will probably net you the best bang for your time and is evidently ridiculously easy to use.