I've used this on the red gel coat of a GTM Libra kit car which was very badly faded to pink and almost white in places.
Not yet completed the car but the sections I've tackled have benn restored to as new condition.
The only tricky areas are the curves around the bonnet and wings where the polisher is too big to reach but that's more of a hardware issue and I'll need to resort to elbow grease!
I need to adjust my polishing technique as it only needs a few drops to cover a large area and I was using too much initially.