Quote - Hello!
I already have Vue 6 and poser 7,Vue 6 has awesome rendering and can easily import poser 7 creation,BUT its VERY SLOW when using radiant light or other lighting speciality on a non-poor PC (1.83 core 2 duo,2GB rams) specially when rendering poser hair!
My question is:
Does Carrara 6 give such beautiful rendering? Is it FASTER than Vue 6 when rendering complex lighting condition + poser character(V4)? Does it import poser 7 PZZ files?

C6 is NOT significantly faster than V6 (except maybe on hair generated in C6). It should import P7 PZZ files (currently still broken, fix promised soon), but it will not handle external morph binaries, dynamic clothing. Transposer is available to fix some of these problems if you also have a previous version of Poser but it currently makes a mess of C6 hair if you want to import an animation.
Quality is something personal. For me landscapes are still best rendered in V6, inside shots in my opinion in C6. Overall the difference in quality is small (but so is the difference in performance).
My advise would be to stick with what you've got. It won't get better, ever, until we get even faster processors and more of them with lots and lots of memory (for an affordable price).