After my car reversed itself into the garage about 6 months ago (yes, the handbrake was on) I bought a bottle of t-cut and the scratches still have not re-appeared as I expected they would after a few washes. Whilst I was in halfords I noticed a more specialised scratch removal system. It was only about a tenner from memory and looked quite complicated as it came with all sorts of little potions, etc. They did have specified colour matches for seemingly all modern cars so that could be worth looking into if the t-cut doesn't help enough.