For a 55w kit, i would recommend running a wiring harness. This basically plugs into the headlight socket but only uses it for the signal and hooks up to the battery for power. I have ran the same 55w kit on my 04 mz3 and my 2012 ms3 and it hasn't caused any issues. The 55w kit may melt wires or not start correctly consistantly without the harness as the kits take alot of power to start but then the power consumption actually goes down to safe levels. I would run a 55w HID kit before i ever ran those 100w regular bulbs. Those will mess your car up. They either melt wires, melt housings, or just straightup shatter.