Hi guys just wanted to know which one would you use and why.

Virtual Server and GSX aren't in the same market. Virtual Server's competitive product is ESX Server.

GSX is a good product if you need to deploy a couple of platform-dependant products in a test environment but are short on hardware, but it's not stable enough for production. VS 2005 and ESX are production-quality products. Personally, I prefer VS 2005, as I have had a lot of issues getting and keeping ESX up and running - it's really picky about hardware support. However, ESX has a lot lower overhead than VS, so it can potentially run more efficiently, especially with a large number of VMs running on it.

I have to asking something as well, simply which is fastrer VMware or V-PC 2004 ? im not asking about compatibility or anything else, im just asking about the performance which one do you think its faster ?

VMWare ESX is the fastest, because it runs on a stripped linux kernel. Next would be VS 2k5, then GSX.