install or upgrade your distro?

When a new version is released of your distro do you do a clean install or do you upgrade?

As crazy as it sounds, with the prebuild distros like Debian Ubuntu, Mandriva, PCLinuxOS … I will do a clean install.

My reasons, you have more control over what is getting installed usually. [ Ubuntu and PCLinuxOS don’t give you that same luxury, but their upgrades of prior releases introduce conflicts with software versions from it not being a clean upgrade. ]

Since I’m going to have to reconfigure everything after an upgrade, and remove the garbage installed I don’t use, why would I do an upgrade instead of an install that lets me stop the software I don’t use from installing in the first place?