Put version E in about a year ago, it does help u defrost the windscreen a little quicker, but as said its lukewarm, its a 1kw heater which on 12 volts can draw 80 amps, VW changed the spec after a few years due to poor connections heating up and causing fire, unfortunately if you want to add to gti you will need version E as it connects to can bus version F runs off diesel ecu, so cannot be Retro fitted, there also really hard to come by as everyone has F's but no E's
