I have about 8x separate XP machines in VMWare workstation for each manufacturer, and absolutely recommend it. Running win7 64bit as well, is superb!
I have a core7 with 8gb of ram, have often had 3 VM's open with a little impact, but generally no issues that are as frustrating as fighting install issues, slow boot-up etc compared to a sluggish machine.
I changed from player to workstation, to try and get some support on USB issues that we have been having with Omron, but not followed it up yet. There is not a huge advantage going to workstation if you don't need the few extras that it provides.
Have also uses the XP mode, and that is pretty good too, but VMWare seems to have a better feel.