i have a full bra for my GT. indeed, you need to take car with it; in particular, the paintwork needs to be perfectly clean before fitting it, to avoid scratches. it probably doesn't suit people using the car as a daily driver; for me, i nearly always only drive the GT in fine weather (not rain, let alone snow), and my car is kept pristine in a garage with a car cover between drives.
move forward a few years, and with my 159, i bought a clear film kit. i am very, very happy with it; a friend gave me tips on applying the bonnet piece (he works with graphics on vehicles), then i applied the rest of it at home.
there are presumably similar kits in the UK, or you can probably order from this place in Queensland, Australia. they have a GT kit (i have thought about applying it to my GT, but meh, i have the bra): Duco Scratch Online Store:
the front of my GT is virtually pristine (as is the rest of the paintwork). not sure how yours compares. i only use the bra when driving on the highway. if i'm attending a 'show', i take it off when i arrive. my car's won a number of awards.
i totally understand the usual response about them being 'ugly'. fortunately, my car is black; however, my local car bra producer offers them in heaps of colours now.
i dunno, but i rather have 'ugly' than a badly stone chipped car. but as i said, now that clear film kits are readily available, i'd go that option instead.