In reply to TobyA:
I normally wear my harness from the start on an alpine day, it seems easier. Maybe I'm just lucky with my old harness but I've never found it uncomfortable. However its the days you don't think you'll need a harness that really catch you out, like planning on soloing a route but then the ice turns out a lot harder than you expected.
I think my keys are low weight, low bulk, and lowish price. I'm not sure about whether I want to use it for Scottish winter climbing, that hadn't really occurred to me but if people reckon the DMM one or similar would be comfortable enough then it is a possibility. That would mean more gear loops the better.
Luckily you haven't complicated my decision much, although I would like an Arcteryx harness one day that one looks a lot like the same thing for twice the price. =]