Update - One year later the calipers look like I just painted them, wheels remain virtually dust free between car washes, all round a great experience.
Now don't attack me but I just bought an '08 Audi TT/3.2/M6/AWD as a year round vehicle (keeping the Z4 as my sports car
- not leaving the tribe). I've already bought another G2 paint kit (red again) and some ceramic brake pads (Hawk this time), so I'll be back to my DIY to remember how I did the paint job last year).