I'm suffering through this as well. My experience is that any reboot or suspend and resume triggers extremely heavy hard disk usage, dragging the VM to crawl. If I make some changes to the VM config (video memory, reinstall tools, etc), it will speed up for the next reboot/suspend, but the next day I'm back to super slow. After 15-20 minutes of this heavy disk thrashing, the VM(s) go back to normal speed. I've tried just about everything. I've changed every setting in the config. I only run in Window mode, not coherence. I don't have any of the sharing features turned on. I've verified that Spotlight and Time Machine are off for my VM directories. I've tried with anti virus on and off, even trying multiple different AV programs. I run 4 VMs, usually 2 simultaneously, but each is allocated 940 MB RAM and I've got 6 GB in my machine (quad core mac Pro). PD3 was great speedwise for me.