I really wanted to like this. It is a great price, SUPER bright (blindingly so). Lots of modes. Looks like it's built solidly.

I just cant recommend it though. The mounting is poorly designed.

Big stretch grommets hold the light to the handle bars. After a few minutes or a good bump, the light is facing the ground.

The worst is the battery holster. You cant remove the battery from the holster while it's attached to the frame. The holster is held on by really annoying, really long, strips of Velcro. To attach it, you have to feed the Velcro around the frame, then through a buckle, then double it back. Meanwhile the Velcro is sticking to itself and refusing to go through the buckle.

I can't leave the battery on the frame, it will get stolen. So any time I need to use the light, I have to attach the holster, travel, and remove the holster. I have to fight the holster on both sides!

Really wish I spent the money to get a light the that had a battery built in.

This product is 4 stars, but the company's tech support and passion is 10. When we were given the opportunity to request extra rubber bands, we also asked them about making available a lense that would diffuse the light horizontally instead of the supplied spot light pattern. When we go out on the trails at night, we need much more peripheral to be illuminated. Well, this company sent us the extra bands plus new diffuser style lenses for both of our kits!

Oh! Do not leave the battery pack on your bike after riding, especially if your bike will be in the sun the next day. Even if the battery is fully charged, the sun/heat will drain it fast. The next time you go out the light will last only about 5 minutes. We found it is best to keep it connected to the charger until ready to ride. Unfortunately we don't know the long term harm to the battery cells by doing this.

We also are wondering if the battery power is being reduced by just having it connected to the light even when not riding. When you first connect the battery to the light, the button on the light will illuminate green. That does probably drain power, so to make the green button light shut off, toggle through the three light modes until it is off. I can foresee an issue where someone may put a charged battery on their bike, connect it up, then go biking days later... That green button light stays on until you toggle through the modes!

If there were a way to connect and disconnect the power to the light via a switch on the cable, or maybe an easier way to disconnect the plugs while they are on the bike, that would give peace of mind. With electronics, we don't always know what circuits are partially "live" and sucking down power.

I would love to see a side pocket on the battery packs that is elastic and holds some of that excess cabling.

Over all the light is a good deal for the price and looks identical to the brand Magic Shine which is one I have been using. The charger and battery are interchangeable. I will likely continue to use the Magic Shine unit with this new Bright Eyes battery pack until the light fails and then switch back to the Bright Eye's light because its a bit dimmer and narrower beam. The LED on the Bright Eyes is about 50% the size of my Magic Shine but the light emission is probably 75% so I suspect that it is more efficient and may extend battery life for longer rides.

Light performance
It's definitely not 1200 lumens, or rather I can say that I have a Magic Shine light which was claimed to be 900 lumens and this Bright Eyes light is noticeably dimmer. Also it's main focus of light is tighter than I would like meaning when it's on my bike and pointed on the road at a distance which the light is bright enough to see the road (approximately 10-15 feet in front of my bike) it's beam is only about 4 feet wide.

Lighting controls
I like that there is an off setting, or what appears to be an off setting. I have not left it plugged in more than a few days to see if it will die, but it seems one can leave the light all plugged in on the bike and need not unplug it to turn it off. I prefer a slower flash setting than this unit has but it seems to be a standard rate for lights currently so I'll deal with it. High vs Low are acceptable difference in brightness, meaning Low is still usable.

Mounting
The mount is same as the Magic shine unit which uses a large rubber band / o-ring type thing that you pull tight around the handle bars. In comes with more than one rubber band which is good because they break after a few years of use (save them in a safe place). Also noteworthy is before they fail they get loose and the light can move on bumpy roads. You can fix this with some black electrical tape, it's not elegant but it works. The battery has two velcro straps which on my Magic Shine eventually failed (~2 years) and I just used 2"x 8" piece of velcro which I am using on this unit now so I don't expect it to fail.

Battery
I have not been able to test battery longevity yet and it's hard to compare to my current light because it's older. I'll post more info later.

I bought this bike light because I would be biking into work in the dark (and often, home in the dark) most days, and needed something for this commute, which is about 20 minutes each way. This light easily serves that purpose. I typically charge it every night, but occasionally I would forget and it never ran out of batteries on me the 2nd day, despite me always having it on the highest setting. I typically don't use any of the other settings, though the lower power setting typically does put out enough light that it wouldn't be an issue if I had to use that instead. I don't find much use for the strobe function, but it's available if people are interested.

In terms of downsides, the battery pack is a bit cumbersome, but it works fine and provides a long enough battery life. the attachment to the bike handle works fine but moves a little bit going over bumps. Otherwise, I've been very happy with my purchase

I was worried that I bought something I wasn't going to like so I tried to cancel my order but it was too late. I still ordered the cateye 800 and planned to return this one. When it came I said, what the heck I'll check it out. Wow! What a great bike light! I have been following the instructions to a "T" because people said their batteries died and what not, but I have had zero problems with it. Very very bright and easy to attach. I gave it to my girl friend to put on her bike and she has a basket up front so the external battery is not an issue at all with her situation. Provides plenty of light to ride down a dark bike path at night (not dusk, we're talking NIGHT) with no additional lighting. We only go about 30 minutes so I can't speak to the battery life, but it's a great bike light for this situation. I wouldn't want an external battery on my bike but with the basket it doesn't really bother her at all.