Id normally rip people to pieces for the good old "resistor chip" but as you seem a little naive... and im tired lol
Heed foxspeeds comments, these things are bad news and will lead to potential problems with your engine, bore washing is probably the thick end of the extreme but it can impose other problems, and to be honest it will mainly clag up the 02 sensors and either cause them to fail or force false readings to the ECU.
Just because something is Max Powers Best Buy Performance Mod 2005 Gold Award winner, doesnt mean its any good... nor does the eBay sellers 10,000 feedback and the "thousands" he has sold resulting in 20% bhp 30% torque and another 2 inches on your pecker.
Proper tuning is done by proper garages, by men with qualifications as long as their arm and the proper top of the range equipment... yes you will be spending easily into the 100's of pounds of your hard earned, but id rather have nothing the a £5.63 +p&p eBay special
My advice go onto eBay (or whever) give the seller bad feedback, call him a twunt and research a proper remap
Im not having a go either pal, just dont like to see the inexperienced get duped by the same garbage and false claims over and over again.
Fit ****e to your engine and it will turn to ****e, Also dont forget its a Renault... so its fragile to start with, without adding cheapo gimmicks to it!