The reason why it's not a high profile mod is that if people get this wrong then its a sure fire way of finding yourself in a ditch..
There's a few different servo part numbers which have been proven to work and some which will affect the balancing valve on the MC which will DEFINETELY affect the braking I the car in an adverse way
So if somebody wants to upgrade then there's a process of chassis number/check/ supply for all the right reasons
The adaption plumbing is not an OEM part it's made by me (and Alex now) and its very unlikely that he or me will supply you a pipe on its own as they're a pain the arse to make and in some way if your chassis number hadn't been checked we'd be facilitating an unsafe state and who wants to do that???
Such is the nature of modding/Internet/forums there would be a good chance of the wrong part numbers being distributed as good when in fact they would be bad and people getting hurt
Its a worthwhile mod IMHO, the analogy being if you had a target BHP figure for your engine and say you wanted to make 250BHP would you do it with a KO3 or a KO4?