got a chip on my swift gti, not no crap chip tho, dont trust them, mine is a fully remapped ECU by SUPERCHIPS....its not about the bhp with chips, its about the driveability and the way it completly changes the way the car drives, really sorted out alot of problems i was having with the swift as it was very lumpy due to cams, forged crank nand pistons, decat etc etc..car pulls from alot lower down in the rev range and even makes it bette ron fuel, you must service your car on its correct intervals as it will wipe all the ecu saftey barriers that the manufacturer instal...it does this so it can get the maximum out of the fueling etc possible
a simple chip change wont affect anything and wont need re mapping each time you mod, but each car takes to them differently, i aint bothered doing it to the golf as i plan on transplanting a 20VT which will be superchipped