I won't say that I'm having no problems, but they aren't much worse than what I've endured in Pro Pack.

Win98 First Edition (I know, I know ... I'll update any day now, I swear ....)
512MB PC133 SDRAM
AMD Athlon XP 2000+

My last big animation project (640x480, 40+ seconds, ~1200 frames, raytraced shadows and refraction) was rendered in Poser 5 in a leisurely-paced four days, although I did most of the scene composing in Pro Pack beforehand.