I have some time this morning, so i decided to try the new BackTrack 5 on top of VirtualBox. The installation is pretty straightforward and it's less confusing than Ubuntu even though it uses the same base (Ubuntu 10.04 LTS).
After i logged in to the desktop using the Live CD ISO (I picked the KDE version), there's only a single desktop shortcut, which is a shortcut to install BT 5 on hard drive.
I had problems when installing Ubuntu, mostly when setting the timezone since it tries to connect to the time server and it usually not responding for some time before it become active again. This doesn't happen on BackTrack 5. The longest part is when the installer stopped at 99% saying "Almost finished copying files...". I think they are still doing background process and it tried to connect to the Internet.
Once this is done, i should have BackTrack 5 installed.
If you would like to install Ubuntu-based Linux distributions, it would be a good idea to disable your network card prior installing if you don't have a good Internet connection. It will make your installation much much faster and you can configure your network card after the installation is done. This way, you won't stuck at installing phase