Hello, I'm new to CG and I want to buy Poser for personal use (for the time being). However, I don't know which version to buy. Should I buy Poser 4 or Pro Pack or Poser 5? I understand that Poser 5 has additional features over Poser 4, but that it also crashes a lot? And what are the differences between Poser 4 and Poser Pro Pack? In short - which version should I buy?... Thank you. (By the way, I'm using Pentium 4, 1.8 GHz with 384 mb of RAM, Windows XP)