As a matter of fact, yes they do - SP3 is the best of the XP runs. And I do IT support for a living as well, and am directly responsible for ... quick count, about 300 workstations at six locations, which is about maybe 5% of my organization's total number of deployed workstations, all connected to a MS ActiveDirectory domain.
At any given moment, if I do a spotcheck of our trouble-ticket board, we will have maybe 30 open trouble tickets enterprise-wide. And yesterday, there were NONE in my area of responsibility.
Yeah, XP SP3 works. Damn well.
I wouldn't touch Vista, however, with a ten-foot pole. Windows 7 is what Vista SHOULD have been.