Terrible. It's slow and bloated. Windows 98 is far less bloated than it or even XP. I tried installing it once and it crashed my computer and fried my motherboard. My friend actually died from installing it.
It was the last sentence that got me
MS (finally) did right with Vista 2. It runs very well on modern machine and even ok on some old computers I fixed for my friends and family. By old i mean 2003-2005 and 768 MB or RAM, though the aero is turned down.