As Dinx said - I have the 256mm Black Diamond/Predator/Braided hose set up on my mk1. There is still a spongy feel to it, but it will stop you a lot better than a standard set up. And it will eliminate the brake fade that scared the crap out of me several times.
The conversion was carried out by C&R Enterprises in Notts, and they look nice and meaty behind the 14" wheels.
Iy is possible to do it yourself, but obtaining the carriers was a job that even C&R found difficult.