I know the subject is LEDs, but Aviation Research Systems, Inc. switched my aircraft to halogens when my Pulse Light mod was installed a couple of years ago. I've been quite impressed with the reduced current requirement and the illumination of the runway during night approaches.
On a related note, our airport (KPUW) was an FAA test site for LED taxiway lights. We just loved the quality of the light, but the failure rate was so high on the individual lights, that the entire system had to be removed and replaced after only a year of operation. It was a heat issue that created the failures and heat dissipation may subsequently be an issue for enclosed case aircraft LED landing lights.