not very i dont think,
there was one a split second performance a while ago, hard to explain but it was mostly made of strip's of metal, abouts 4, that went from front to back and they were bent, then it had acrylic and then the whole things was coated in fibreglass, the brackets etc were welded to the metal strips
F**K its hard to explain lol
i think it was just a dodgy job of it but they said they can order them in so i dunno :S