I must say that I've been playing bunches of ZDoom after I figured out how to get it to compile. I also have PrBoom and Eternity installed. The one thing I really wish is that I could make all my Dooms look at /usr/local/share/games/doom/ like PrBoom rather than me having to create softlink all my WADs into all sorts of hidden directories in my system...
At some point, I plan on trying Doomsday too, just for the sheer eyecandy factor, though I've been led to believe that Doomsday is bad for playing 3rd party WADs with...