the rs tuner is said to be about 6-8 bhp gain
however it is half the price of superchip and its made by someone who does nothing but map renaults (i think) which means hes a specialist unlike superchips who, if asked, would map your kettle to get a better 0-boiling speed! not to mention, rs has a fault code reader, a live data setup and a performance analyser which will tell you your bhp etc. plus if you really dont wanna go down the rs tuner path, take it to rstuning for a RR remap whos rep is huge on here.