Threadless or threaded headset

right so it's just a matter of taste then? nothing like threadless headsets are cheaper, or you can fit a wider range of different bars, etc?

because if it really is just a matter of taste, I think I'm getting the threaded one - threadless headsets just look too chunky I think

No. 1 1/8" threadless headsets are a lot stiffer, and in lighter. They also are more widely availible, and have a more standardized clamp size. So are easier to live with. As Hippy pointed out, headset adjustment on a ahead set-up requires a couple of allen keys (found on nearly all multi tools). Yet headset adjustment on a threadless set-up requires a (preferably two) bloody great big spanner.

Havin said that, I have a quill set-up on my fixed. But only because thats what aesthetically suits the frame.

1.1/8" ahead > 1" threaded