I would recommend C5 Pro for the following reasons. 1. It is less expensive than your other choices. 2. It handles Poser 4 5 and 6 files natively 3. It has an awesome rendering engine, very fast and high quality. 4. It's user interface is simple yet very very powerful with a very low learning curve compared to the others. (It is a bit closer to the way Raydream Studio used to be, rather than C4.) 4. It has excellent modelling capabilities for the money. 5. It has great skinning and lighting options. And its good to hear that the volumetric clouds will be fixed in the next patch. That one bug has been driving me nuts. Give the C5 demo a try, You'll like it Im sure.