This is on my short list of next cars.
I don't think the Scirocco is hairdressery' at all IMO. It's in fact one of the few 'coupes' that I've looked at that houses two adults comfortably in the back, just like in the GTI. I've sat in the back of my car only really to clean it, but I'm always impressed how much leg room it has and how comfortable it is - much like the drivers seat
I've shortlisted the 123d and 325d/330d but I've heard both of those are cramped in the back, although the boot space varies.
I didn't like the Scirocco when it came out in all honesty for around 6 months but having seen some tastefully modded, they've really grown on me.
Like you I'm looking at the 170 TDI too. With a Milltek and a map I'd like to think I could reach around 230hp and nearly 600 miles to a tank certainly adds to the appeal, or I probably wouldn't be looking at a diesel. It'll be my first derv as well
GTI to Scirocco is a decent route so no reason not to as far as I can see
I think two or three on here have done that exact change.