The BEST advantage is gained from a decent ecu, this will SAVE your engine as it can be set to AUTOMATICALLY back off the power if EGT goes too high.
Also useful as a tuning tool, as a given state of tune/parts will give a certain "correct" temp, if it goes off this but not dangerously so you know you have a problem like a dicky lambda etc, or whatever it is, as temp will stay fairly stable under normal use.
Only £115 NEW(audi), but how many ecu's can use them ?, fortunately my one does.
tabetha