I also had to Seat them in properly, this was the annoying part as my HID bulb was not exactly the size of the factory size (it was after market)

If I could do it again, I'd get the more powerful 55 watt versions over the 35 watts - I noticed that the factory BMW/Acura HID are far brighter than my 35 watt HID

Lastly, my Ballast keep dying every few months so I have to do the warranty replacement which requires disassembling and reassembling new ballasts every few months..