I'm trying to make a decision between these two lights. I've spent a few hours reading about them on the web, but I haven't found anything definitive about how these lights compare to each other. They are both LED lights that use a single LED. They are reputed to be significantly brighter than other LED-based lights. They both use 4 AA batteries for power. I believe both these lights use the same LED, and they both have specially designed lenses/reflectors to maximize performance. Apparently they both throw a fairly bright, but narrow, beam. I get the impression that the Nitehawk Emitter may give a little better light, but its seperate battery case doesn't seem like as good a design (some say the clips that hold it together seem like they might fail, and that the batteries rattle around on rough roads). It also looks like it would be more bulky to carry in a bag. I prefer the design of the Cateye EL500, but don't know if it provides performance equal to the Emitter. The Nitehawk Emitter also appears to be marketed by Performance under the "Gen3" name. It is available in standard and "digital" versions. The digital has more brightness options, and apparently has some sort of regulator that minimizes dimming of as the batteries are used (they maintain the same brightness until the batteries are almost exhausted instead of gradually dimming). Apparently these lights all provide outstanding battery life and adequate light for many riders (we'll be riding at fairly slow speeds on paved bike trails and lighted neighborhoods).
Has anyone compared these side-by-side? I'd really like to make the right choice and order a couple of lights for my son and me, but can't decide which to get.
A while ago I compared them side by side at a bike shop. Honestly, I couldn't decide which one was better than the other. Cateye's beam focuses on a small area, and it is brighter on that area. Nighthawk's beam is wider but it didn't seem to be as bright as cateye. Nighthawk is a little purple, and cateye is white. One thing I am sure is they are not halogen alternatives as they are advertised. They are bright, but I think not as bright as 10w halogens.
Well, if you are planning to order online, I strongly recommend you go and compare them at a bike shop first, and see for yourself. Sorry for not being very helpful Good luck!