'Off road' bulbs are usually much higher wattage, which the stock harness can't deal with.I've had good luck with Osram Nightbreakers for halogens and Xenarc extreme for the Xenons. Philips also do a similar range of whiter than OEM bulbs.Thanks for your reply mate, yeah that’s one thing I was concerned about was the very high wattage of the off road bulbs. Guess I’ll swerve them and check out those you recommended! Thanks