I've been riding and working on bikes for over 35 years so obviously I have had plenty of experience with threaded. I recently built up new bikes for my lady and myself with threadless and I must say I really liked the way that stuff goes together. She and I each tried three of four different stem angle/length combinations, and that would have been a real pain w/o the easy changablity of threadless. Of course, now that we have settled on our layouts that point becomes somewhat moot.

There was a long thread about this in the Mechanic's section (my usual haunt) a few weeks back, and of course we did not really come to any concrete conclusions but there were some interesting observations.