Basically... No difference. Initial load as slow or slower. Subsequent reload is faster, but system seems slower after Poser unloaded - need to investigate, but have to run P5 to do that, and really don't see the point (to run P5 vs. P4). Run time performance exactly the same - still click and wait a second or 2 for effect to occur, or rather, click twice to reset the focus. Still consumes 98-99% processor during load, render, etc. (which might be acceptable if P4 compatible renderer was faster than in P4 - but it isn't). Still doesn't allow control back to Windows for screen refreshes, etc. Still, ... Well still the same IMHO, an ill behaved application that's almost ready for initial Alpha testing, and with some basic updating to bring it up to current Windows programming specs/standards could soon be ready for some serious Beta testing. :-) But in terms of applying SR3 to fix one of the very few specific bugs that were addressed, why not install? Win2k SP2, 1GHz/1GB. P5 was always stable on this system in terms of no crashes, no BSOD, but dog slow. But per CL posting of last few days no-one complains that its slow thus it presumably will never get fixed. (CL please see the thread of happy users as an unbiased control, even they say it's "Slow, OK" and "did most of the scene composing in Pro Pack beforehand", "slow transfer between anything", and similar. And this from the happy users, not the EVM!) 8.25 months ...