Funny I was just reading all about this earlier today without seeing it on here,,, I've had a HID kit on a car before and it was quite cumbersome to fit the ballasts event with all the engine bay space. I also had to drill the cap of the rear of the light to fit the cables - so I was looking at some Philips Xrreme Vision 130 instead - trying to get a better light plus something more white light xenon.Some yes, this one, not so much.
I see a HID conversion on ebay, I may need to be the guinea pig
The HID was too blue (even though rated at 5500k) and I used to get a lot of flashes from not so happy motorists. Also, on my last Harley I had their LED headlight as an upgrade and it was rubbish! Looked way cool but had a very narrow spread, way worse than a stock light! I had a look at LED H4 bulbs today but all reviews say they're crap too.
These are the Philips
Philips X-treme Vision 130 9003 HB2 H4 Twin Pack Car Bulbs Direct