I started buying high-powered LEDs a while ago for use in the lab at work and became somewhat fascinated by them. Decided to try a few on the car, starting with interior lighting, and continued to be impressed - gradually working up to the point that the only non-LED lighting on my car now are the headlights and driving lights. Have now started on my bikes and thought I'd share the results. Attached are two pictures showing both the standard halogen bulb on my GPX (on the left), and a replacement LED bulb (on the right). Both pictures were taken within 5 minutes of each other with identical camera settings (iso, shutter and aperture) so the fact there's very little difference between the two at least proves I didn't make things worse. What the pics don't really show is that the LED bulbs are in fact slightly brighter (evidenced by the light meter on my camera), and since it is a red LED bulb there's also a noticeable improvement in the colour of the brakelight (forgot to set the camera white balance to manual so it's not that obvious in the photos). So if they're only slightly brighter and more red why use them? The answer is in the lag time. I'd never realised just how long a standard halogen bulb takes to light up until I compared halogen vs LED side by side on my car. To me that slight decrease in the time it might take some dumb-arse cager behind me to notice I'm braking is more than worth the money IMO, and the fact the bulbs will possibly out last the bike is also a bonus. Place I've been buying them from is an ebay seller based in Hong Kong: http://stores.ebay.com.au/warden-jp2002 The globes I've been using are the 13w "High Power" 1157s and 1156s which seem to be only sold in pairs (not a problem for me given both my bikes use the same brake light bulb ). Can't speak for the cheaper refractor SMD based bulbs or the more expensive "ultra power" bulbs, but have certainly not had any problems with that particular seller. Next up will likely be some LED indicators for the Kat, but only because the original indicator relay was rooted and figured if I was gonna replace it I may as well buy an LED specific one (about $12 from a Thai Ebay seller). I have more than enough standard 21w bulbs spare now to keep the GPX indicators going for a very long time .