I've been running VMware on my openSuse box for several months now. It has been rock solid and reasonably easy to use. This week, I took the liberty of upgrading to VMWare server 2.0. WOW! What a difference! The new console is SOOOO much better. I was able to move my old WinXP laptop to a VM image using VMWare converter. I then was able to work from my Vista laptop, remote to my WinXP image across the network.
This proved to be a much better solution than swapping hard drives around like I had been. The WinXP hard drive is a 5400 RPM drive. The new WinXP image runs on mirrored Western Digital Caviar 640GB 7200RPM drives. Not to mention the server is a quad core with 8GB of RAM. This is my WebSphere Portal development environment. It is MUCH faster in a VM than on my old disk.
Now, I'm shopping around for a gigabit ethernet switch and some addtional WD drives to spread out the IO. Even though I was pleased with the new console, I would venture that it will be significantly faster on Gb Ethernet.
If you are currently using VMWare server (the free edition) 1.06, you should seriously consider upgrading to 2.0. It has made my development efforts MUCH easier. Thanks VMWare!