Many of you have asked about, and tried, halogen bulbs, HID bulbs, and LED lights. I recall the main
advantage to the stock halogen is that there are a couple of options on brightness and length of life, but all are easy to install. Just plug in the new one.
Those who have tried the HID setups have found the cost maybe $40-100 or so. The installation wasn't too bad other than finding a place to put a ballast. The biggest drawback is the reliability, maybe more on the cheaper sets, I'm not sure. But they do give much light projection. Mine kept cutting off power, so I took it out.
Then comes the LED headlight. It is the latest, is shock resistant, and will outlive your next three bikes if you keep switching it around. But they can be pricey, or not. The "nots" are the ones that are just a LED bulb you stick in your stock housing. They work and are bright. The problem is the housing isn't designed for the reflection and there is a lot of high glare toward oncoming traffic. To solve this, some replacement housings have a built in "shelf" in the middle of the reflector which keeps the low light aiming down and lets the high beam shoot up more. Or you can buy a full housing with the LEDs already inside and shelf that works the best and easiest.
The problem with the better LEDs is the price. The most expensive are sold by the Harley dealers and (if I understand correctly) are around $500. each. These are an older brand, but costly. A cheaper brand, which many seem to find is pretty reliable, is the Trucklite Phase 7. If they are labeled Kuryakyn and are sold by the on-line m.c. suppliers like JP Cycles or Dennis Kirk, they usually go for about $260. plus shipping. If you get the Trucklite brand under that label, you can buy them on Ebay for $163.and up. My last one was used and I got it from a re-seller and paid $85. total.
But let me tell you, the difference is tremendous. You can link in this site to photos of comparisons, but in all, there is a good white light (not blue or yellowish). I think I like most the cutoff where the low beam stops. I mean, you could light up someone's bumper without hitting their eyes (I would suppose, I haven't tried it specifically). I have ridden on back roads where the highs would shine a half mile down (I'm guessing) and not blind any oncoming cages when I switch back to low. Another advantage is the side light. It lights up the edges of the road which would help to locate deer waiting for a bike to come by before crossing.
This type of light should be on the wish list of anyone who rides much at night. They are a little more hassle on install as you must disassemble the light housing ring to install the whole new light housing, then re-adjust. But well worth it.