I've got 6000K's in my Jag (35W). When it comes to HID bulbs, there are lots of options out there. I guess I have to ask what you are looking to get out of the HIDs? If you are after a specific color, tell me what you are looking at and I can probably tell you the color range to look for. ANother thing that I will highly recommend is when you do the HID conversion, you look at doing a relay harness for the HIDs. Will the HIDs work just tapping into the stock wiring? Yep, they sure will. BUT...... (you saw that one coming didn't you?). Keep in mind that when you turn on your HIDs, they are going to be pulling about 40 amps for the first 2-3 seconds. The headlight switch is not really rated to handle that kind of load. So, for awhile the switch will handle it,but over time, the headlight switch is going to fail on you. Doing the relays, you are taking most of the current and bypassing the headlight switch and only using the headlight switch to run the actuation portion of the relay. The rest of the power is coming straight from the battery. This leads me into the second part. HIDs love high voltage. What I mean by this is that HIDs will last longer if you can keep them at say 13.7 VDC than at 13.0 VDC (due to line losses in the headlight switch, wiring, etc). Using a relay, you will have less wiring between the battery and the HIDs and less switches too. This all helps to keep the voltage as high as possible.
If you want to know more, let me know. I'm sure some of the other members will tell you that I can give you a little lesson in subjects like this.