Ok.....Stern is absolutely correct...those "plug and play" kits that drop in where a halogen bulb used to be are TERRIBLE!!!!!!
They are the WORST thing for dazzling oncoming cars, and they make me want to smash the lights of any car I see with them.....at the very least they usually get a nice dose of high beam from me!
Properly fitted projectors on the other hand.....are awesome.
There are two sites I will reference you to on this one.
www.theretrofitsource.com is a site that sells projectors and bulbs. They do OEM projectors brand new from various cars, as well as repros of hard to find OEMs, and they have developed their own projector units just for retrofitting, including the Morimoto Mini which sacrifices a tiny bit of performance for the ability to fit into all kinds of headlight housings where the bigger ones will simply never fit.
They have various shrouds and other bits too, you can get everything you need for a conversion from them if you want to.
www.hidplanet.com is a discussion forum all about lighting upgrades and nothing else.....there are hundreds of conversion threads on there covering all of the common pitfalls and various ways of doing the job. HID projector conversions, LED conversions, Halogen upgrades, you name it, it's there....
Click and search and read.....
My current daily driver has the best of both worlds....it has LED projectors. The light is INSTANT and the cutoff is nice and crisp. Light is daylight but not blue. I have driven it back to back with the 2012 model which has a Halogen projector and the LED kicks it's arse big time.
Also being an electric car, LED takes less power so it has no noticeable effect on my range......