I recently ran into limitations with Virtual PC on Windows 7 - and have actually found recent versions of VMWare to be somewhat sluggish, even on a fast machine.

Well, I think I've found a third option.

I pulled down Sun VirtualBox (which is free) a week ago, and created 2 VMs for VS 2010 and SQL Server 2008R2.

It allows you to create a 64-bit VM, which (AFAIK) can't be done with Virtual PC. (SharePoint 2010 beta requires 64-bit).

So far, so good. The settings offer more advanced features than Virtual PC. I've only been using it for a week, but have really been impressed with it.

Just curious if anyone has used it - might be a bit premature to say this, but I think it's the virtual software I've been looking for.