I have used the Nanolex trim rejuvenator from the link above, as you can see from the pics my trims looked shot.
Door trim before
I thought about replacing them but decided to try to refurb then first, nothing to lose really. I masked up the paintwork then used 200 grit sandpaper on the trim keeping it wet using plenty of water. Then it was just a case of drying it off and applying 2 coats of Nanolex.
Rear window moulding before
Same again as above
They look not to bad considering I didn't spend much time on them. I'll just need to see how long it lasts, hopefully quite a few washes.