Just curious...how many versions of Poser do YOU currently have loaded onto your computer? And Why?

I've got Propack, Poser5, and Poser6 all loaded onto my computer...primarily because I do animation work and Propack is still the fastest of them all. I use Poser5 whenever I need dynamic cloth/hair in an animation where the background is still because I get wierd image artifacts sometimes when I try to move the camera during an animation with Poser5 (But it's still slightly faster than Poser6). Finally, I use Poser6 to render scenes where there are dynamics involved, and the camera must also move throughout a scene - this option often takes a ridiculous amount of time - even when I use the Poser4 rendering engine - so I rarely render animations with Poser6.

Seeing as how each new version of Poser seems to be slower than the last, I just can't bring myself to give up old versions for newer versions...that's why I actually refuse to buy Poser7...it would just take up more space on my hard drive while I use Propack more than anything. I'm just curious how many others are in the same, or a similar boat when it comes to using multiple versions of the same program?

Thanks so much!