I've bought some from Bruce, and can report this stuff is really great. It turns a limp lexan body shell into a nice hard shell that can be painted the "proper" way, i.e. from the outside.
Bruce's instructions are specific and should be followed to the letter.
Another little tip is to use two very thin coats as this suff can "exfoliate" very badly if the materials are applied too thickly. (my first wasted bodyshell is proof of this!).
Great suff and while your about it get some bodyshells from him at the same time. They are cheap and the detail is very good.
I'm happy to write a review at some stage if you want one, together with TSRF chassis and Slot car heros chassis.