Hi there. Ok so I know about these £4 resistor chips that everyone says are bogus. However I can't find any decent reviews on the obd2 plug in chips which are around £120 Mark. There are 2 companies 'proracing' and 'chippower' who both claim the plug in kit has a stored 3D map amongst other stored parameter corrections.. my question is, for alot more money and an actual plug in kit rather than just splicing into wires for resistance, are they any good?? I am still very sceptical and not sold by the idea however have interest for them if they actually work.