I converted almost all my lighting over to LED and I love it. All my interior lighting (minus the dome light) is LED.

I used SuperbrightLEDs and here are some tips:

- match the LED color to the light color (aka use a green LED for blinker, red LED for brake light, etc)
- use the dimmest or second to dimmest LED as the brighter ones are too bright and also may not fit in the sockets
- try to avoid the LED "towers" for interior lights as they are usually too big/long -- these work great in the exterior lights though

To me, this was well worth the money. When I hit my interior lights with the car off, my ammeter needle barely and I mean barely even twitches. It used to dive into discharge with about 10amps or so...