just to add that some dealers are also remapping agents and therefore help retain your manufacturers warranty
Nope. You need to be a tad careful with that comment.
I accept that a certain few dealers are becomming agents for remaps - and that
the dealer in question will state they will warrant the remap - but that will still invalidate the Volkswagen UK and Volkswagen AG warranties. So that may be perfectly fine if you don't own a passport, and never leave your locality - but if you travel a lot, and break down or sommat 100 miles away from your local - you will get recovered to your nearest. That is exactly what happend to the chap with the Seat Leon Cupra - bye bye warranty, and if you don't actually own the car, bye bye to that too!
one of the chaps on here had his ED30 remapped by his dealer with very good results at last years JKM; think the remap was supplied by Richter
also i think Red Robin's dealer has recently become or was in the process of becoming a REVO agent
But no matter how good Revo, or any of the other remaps are, and no matter how good your local stealer is - it is NOT they who have the final say in warranty work.