The Bluefin is also a DIY job. You buy the handset off them , plug it into your car and it downloads your ECU software, which you then upload onto your PC and email to them. They then email you back ( within 24 hrs I think ) the updated ECU software which you transfer to the handset and plug into your car and bob's your uncle. It is then totally switchable between stock and remap via the handset. Not heard too much about the standard 200 bhp 2.0 TFSI engine but the guys with the 230 bhp Golf Ed 30 GTI's love it and are claiming up to 300bhp from it. The Revo is more expensive but I guess you get the service from the Revo dealer and a rolling road before and after.