Hey Gareth
Glad you like the kit. sorry for the delay, xmas, lack of couriers and an engineer who was busy planning his wedding day didn't help
Just to answer a couple of questions.
The Wilwood kit is a 4 pot setup with 294mm Evo disks. the calipers weigh less than 1.5Kg each. Wilwood kit will fit under some 16s without spacers (depending on the offset)
Both kits use all brand new components with a 1 year manufacturers warranty.
I cant comment on the performance of the RB kit as it's from another trader, but I do know it is substantially heavier than the Wilwood kit and uses second hand calipers. Also, spacers may be required to clear 17" wheels.