IMO the two big differences between poser 7, 8, and PP2010 for most people are that:

1.  PP2010 has IDL and built in GC. 

2.  P8 has IDL but no GC.

3.  Poser 7 has neither but is a lot cheaper now.

 

For me, and someone can correct me on this if I'm wrong, is that IDL still has a few bugs in it (particularly when using ambient objects, doesn't work with atmosphere, etc) and its pretty slow for the current versions.  It also hates transmapped things (in terms of rendering times).  That said it can produce better lighting in a scene.

GC is great but you'd probably need VSS to work with mutliple materials as most mats (like for characters) are designed with a pre-GC renderer in mind. So it has good results but requires more work.

There are some things you can do to give P7 and P8 GC, but that requires you learning to use the mat room to play with mats.  Unless there's a DS add-on, the poser mat room gives you  more options, but you also have to have more know-how for using those options.

A final thing to consider is interface.  Poser has a different interface than DS and that may or may not take some time getting used to.  I like poser's more having started in 7, but there are some people who prefer how DS looks.

WARK!

Thus Spoketh Winterclaw: a blog about a Winterclaw who speaks from time to time.

 

(using Poser Pro 2014 SR3, on 64 bit Win 7, poser units are inches.)