If that bulb is the same as it is in my unit, it's a G4 20w 12v Halogen. I had to replace one over the sink on our first trip last weekend. I also would like to replace them with LEDs. The ones available at the Lowes I stopped at were pretty pricey, and not bright enough for my taste, they were like 2w.
I think in LED, you want like 4w to get similar brightness as a 20w halogen. A halogen will put out like 350 lumens, a 4w led will put out like 320. The temperature designation seems to indicate what kind of color you will get.
To me it seems like the most difficult thing will be to find an led that will fit in that fixture. I don't think the drum shaped ones will fit. I'd like to find one that is flat with all the diodes facing down, but I'm afraid the wafer shape of the ones I've seen will be to big for the fixture. I'm going to take measurements to be sure next time I'm out...
2014 Jay Flight 28 BHBE
2015 RAM 2500 6.4L HEMI, Tradesman 4x4, 3.73
Blue Ox SwayPro (BXW 1503)
Upgraded from an REI internal frame backpack and a Eureka 1/2 dome tent!