I like LED lights, as a matter of fact have Rigid Industries lights mounted in 2 of my bikes.
But for the valkyrie, none. The I/S lights (got 55/65W bulbs) are one of the best I've seen in any bike and the fog lights (35W) work really well.
The reason to go LED would be to have more lumens with less heat? (i.e. in a standard)
For me it is also the obvious less amount of current draw on the wiring system and starter switch assembly, and the LED technology is just getting better and at times cheaper. I will get a switched/un-switched power hub eventually, but the LED headlight bulb will likely be one of my first farkles.