(I tried LED replacements, have a couple over the bed. They were intended to go under sink and overhead ceiling kitchen light, there the most used lights, but didn't like the LOW output of the LEDs. If your really into conserving your battery, LEDs are the way. I picked up a couple of 1156-PCB-W24 led lamps from Superbightled.com. I could use them for low level lights etc, perfect for watching tv but for dicing onions, reading I don't think so. Its weird how bright they are looking at them yet the light out put for general lighting is so low. There a few places that there great for and perfect if you end up with dying batteries somewhere. You can see by them & safer than candles. )
I use Thin Line single tube fluorescent fixtures-power consumption is half of a regular bulb. I discovered when mounting the one under sink cabinet that if you pull the wood trim tape off the half of the diffuser that's covered you get light out both sides, if you remove the shield inside you get even more light dispersed. They use the same fixture for single & double tube lights, on the single tube they cover the diffuser with wood grain tape, I guess so you'll orientate it correctly. Though I recommend removing the tape to increase the light output area (unless you want it directional) -due to the fact you might shock yourself, I don't recommend removing the wiring shield (even though you get better light dispersal).