Aftermarket chips which claim more power and fuel savings are not worth the risk. Most chips increase fuel pressures in a system which already runs 22,000psi in the common rail. The longevity of the pumps and seals running at these pressures are somewhat untested and as such not really worth thinking about (personal opinion only) best thing you can get for a hilux is a nice free flowing exhaust. makes a world of difference and doesn't hurt the engine.