well kenmo i've been using daz since 1.7 and have 2.3, 3.1A, and 4.0 on my pc there are pluses to each of them but i've found ds3.1A the best bet so far sure with the pop out window for the render engine its a little less memory hoggish.  but there are some things that i've tried loading into ds4 that only parts of show up in it as it is now.

 

and i'm not too sure if they've fixed it yet but last time i tried rendering a texture with normals maps in it it would crash every time.  but keep an eye on it and see how it progresses and what avid daz users think of it then figure out if you want it