Hey there, Lyne!  Don't know if relating my own experiences with V6 will help you , but here's what I've observed so far.

For Poser figures, V6i seemed to behave much like V5i... that is, I could load up 3 to 5 DAZ mil3 figures in both, with both getting very sluggish at 3 figures (sluggishness varies depending on how much xfrog stuff is in there). I'm running a dual processor/dual core AMD machine.

The other day I installed WinXP64 for a dual boot configuration,and then installed Vue64bit, and what a difference!  I only have 3GB of ram right now, but even that was enough to bring V6i to life. Of course, all the various bugs in V6i 32 bit are still there in 64 bit.... but my workflow is greatly improved. Needless to say, I'll be upping my ram very soon. :-)

If your machine is 64bit ready, give the WinXP upgrade some consideration.... while also considering that XP64 does have compatiblity issues with older software and drivers (Xfrog and Poser 6 both seem to work just fine under XP64, maybe even better).

Hope that helps!