I'm using Poser 6 and Serif PhotoPlus (which is similair to PhotoShop and PaintShop Pro, but imo much nicer to work with). For me, Poser has every feature need to create digital comics. PhotoPlus is being used for adding some special effects and touch ups. In the past I've used Vue 5 Pro for rendering and creating landscapes/backgrounds. That was before Poser 6 was released. Poser 6 has a light version MicroCosm included, to create landscapes and included many new rendering features, which I liked much better then the ones in Vue 5 Pro. From that time on, I've invested some money into Poser 6 and some add-ons (like MicroCosm 2.0 full version and a number of trees & plants). I'm much more pleased with the results. No need to go from on application to another, everything right at my disposal. I don't see why you would need Shade Pro at all and my advice would be to invest the money put aside for Shaoe Pro into some more poser content instead.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk