personally , Ive never owned a diesel with a chip but have heard to many good stories about quality brand chips , chip it , uni chip etc . Got a mate with a uni chip in his d40 it makes his ute hammer , mine would be done now but all the quality installers tuners are to far away. Mine's got gas injection but I think its a bit more costly these days with the rebates dropping. But like old Tony says you get what you pay for.