I personally want to know what the heck is going on with the huge .mem file as well. I set my VM to grab 512MB of memory, yet Parallels created a 1.46GB .mem file in the VM's folder. Google leads me to this thread: http://forum.parallels.com/showthread.php?t=7180 ...but of course there is no conclusive answer. Meanwhile, I'm with the 'Coherence is an essential feature' camp. I cannot justify having to see a whole separate desktop while running a couple of Windows app when it is clearly possible to do away with it (the Windows desktop, that is). It's great to have Internet Explorer running in VM and Firefox on the OS X running right next to each other, for example.