Hi,
the registry is just a big INI file, and if your software is listed as "installed" there is just another registry entry. So... you know what I wanna say?

But you're right about not installing software, but copying a client from one computer to another when possible. When you don't install, then you avoid installing system DLLs or components which will propably never cleaned up after uninstall.
I also prefer programs that do NOT write to the registry, which use an classic INI-file (as much as it makes sense). EXE and INI-file could easily copied from one computer to another, it's easier to edit options, uninstall means to delete the directory and you can backup everything (even the settings) by storing a ZIPed archive to another harddisk/CDROM.

To get offtopic: I wouldn't rate Bearshare "clean". There is spyware also in the current version. You have to deselect it on install time, every newbie who does not know about spyware is spyed out after using Bearshare. This says nothing about the client itself... it's nice, however, make sure you know what you'are doing.

Hope it helps, Moak

PS: My feature request would be: use an INI file, don't write anything to registry (only automatic uninstall feature, if installed).