VMware vs. VirtualBox on Windows

I've been using VMware Workstation 6.5.3 under Windows XP for a while primarily running Ubuntu 9.04. While it works well, I've chafed at the 2 processor (core) limit and the lack of 3D support (for compiz).

Sun's VirtualBox 3.0.8 supports more cores and has 3D support. The clincher was that it could use the same virtual disk format as VMware so I didn't have to start from scratch! I got the VirtualBox machine pointing to the VMware disk image and installed the guest additions. I then enabled compiz from the System-->Appearance menu.

Compiz worked well but there were repaint problems whenever a pop-up from VirtualBox or Windows appeared. Alt-tab refreshed the screen well though. Shared folders and USB support were different as well but workable.

Some limits that were more annoying were:

• I couldn't set the memory to allocate for Ubuntu to anything more that 1500 MB even though my machine has 3.x Gig usable.
• Full screen mode (no window boarders) only supports a single monitor.
• I could stretch the normal non-full-screen client to span both monitors but then I lost a lot of vertical space to menu bars, etc.

The clincher for me was that I couldn't shut down VirtualBox and use the modified virtual disk under VMware again. VMware would start to boot Ubuntu but GRUB stage 1.5 would fail with an "Error 18".

Thank god for backups...