I love everything about this light but it is not water-proof. The USB recharging is invaluable and seems to hold a charge for plenty of time. The flexible mounting band is easy to attach and secure on a number of bike parts. The light is not the brightest but plenty bright for safe riding. The mounting bracket pivots so you can angle the light up and down while it's attached to the bike.

Only issue is that after one short ride in moderate rain, water got into the housing causing condensation on the lens and shorting of one LED. May just be this particular item but somewhat disappointing. Excellent customer service though.

I've been really happy with this light. I ride 4 - 6 times per week and most of my fall and early spring rides start in the dark. I use this anywhere from 1 - 2 hours per ride (depending on if I remember to turn it off once it's light enough) and have never tested to see how many rides I can get in before it runs out. I usually charge it every other ride, just to be safe, but I assume I could get another ride or two out of it if I happen to forget to charge it. I always choose the slower blinking option. It is BRIGHT and it is easy to charge. I like the fact that it can be attached horizontally or vertically, and it's very easy to charge. The ability to tilt the light is also a plus. The only minor drawbacks I've had are 1) taking it on and off takes a little bit of precise effort and pressure on the release tab. It's a little tricky to put on or off when wearing gloves. Obviously not a big deal. 2) the rubber piece that covers the USB port tore off very easily. It is only attached by the thinnest 'thread' of rubber, so you have to be extremely careful or it will rip right off. This doesn't change the effectiveness of the light, but it might become problematic if I ever get caught in a decent rain storm. The USB port is on the back of the light, so it's protected from the rain, so I'm not too worried.

***UPDATE***
Ended up riding in a decent rain storm during a 24-hour relay, and my tail light did, in fact, short out as a result of the missing USB cover. As I was riding, I was able to reach back and turn it back on, but it would only stay on between 30 seconds and 3 minutes before it would shut off again. I had to switch lights to safely complete my night ride. I figured the light was probably toast and would need to be replaced. I put it aside for about 2 weeks but decided to give it another go before purchasing a new light. To my surprise, it worked perfectly. Turned right on and stayed on throughout the entire ride. I have since used it for an additional 15-20 rides that start in the dark and have had zero problems. If I know there is a chance my ride will include rain, I'll throw some tape over the USB port and I should be fine. I would (will) purchae this again in a heartbeat.

Sometimes simple and low cost are synonymous with poor quality. I'm glad to say that this is most certainly not the case with this product!

I was actually looking for something that could be mounted permanently, because I don't want to have to deal with trust issues with something that just straps on. Turns out, the rubber strap on this works just fine! It's wide enough to get some good grip, tight enough that it doesn't move, but not so tight that you have trouble getting it on.

The LEDs are no joke -- they are BRIGHT! I haven't tested the runtime, but I can say that it stayed plenty bright for a more than 20-mile ride (which was about an hour and a half). I have a feeling the runtime claims will be fairly accurate.

I like that the light can be oriented either vertically or horizontally. I would prefer the vertical orientation, but as I have a small pack mounted under the saddle, I had to orient it horizontally so it wouldn't seem like it was mounted too low. This was a clever feature. Plus, the bracket tilts!

The USB charging was a MUST. I like that it uses a Li-Ion polymer and not a cheap-o NiCad or NiMH array, which means it has a charge/discharge circuit to prevent over/under charging (just like your laptop does). I know the battery will stay in top shape for years without worrying about charge memory memory. As a bonus, the charge status LED is great -- I know when it's charging, and when it's ready!

My only complaint is that I don't like there being only one button for powering on and cycling between modes. To switch between steady and flashing, you have to hold down the button when turning it on. It's easy enough, but I'd rather have three buttons: mode, brightness, and power. This is because I am often already on a bike ride when dusk approaches, so I'm fumbling around behind me trying to turn it on, and I'm never sure if it came on the way I had it set last, or if I may have accidentally change a mode. And it's not easy to get on and off while riding, so I can't just pop it off to turn it on and pop it back on. However, I'm sure I'll become accustomed to it quickly enough and this won't be a problem. Oh, and I must say that the button is easy to feel and manipulate, at least.

Overall, this was just what I needed. It's was a well thought out design, built well, and works perfectly. It was worth every penny and more, and I'll recommend it highly to anyone. Blitzu is a name I'll certainly buy again. Speaking of, if you need a headlight to go with this, I'd recommend the Blitzu Gator 320!

Very effective light! The ability to change intensity helps to conserve battry when needed. However, even the lowest setting is bright enough to actually illuminate the ground behind me, which actually increases my visibility from the front as well!

The "flashing" settings have 3 speeds: slow, fast, and strobe. I wish it was "low strobe", "medium strobe" and "high strobe" though. Low flash frequency may present danger since you're practically invisible during the "off" period, and the only reason to use it would be to conserve battery, and low-intensity strobe mode would achieve the same.

Also - be careful when removing the rubber plug covering the charging port - yank to hard and it will fall out! A minute of poking it back in with a toothpick put it back in, but I didn't expect it to be attached that loosely. It stays in now though.

However that's just my 5 cents - I'm VERY satisfied with the light and I will continue to use and be very happy with it

I am impressed by how bright and attention grabbing the tail light is. I installed it on my cycle and had a friend ride as I followed in my car. Low strobe with the light attached to the port or left seatstay seemed most effective. I have a tool bag under the saddle which makes mounting the light on the seat post impractical. I thought the hi flash strobe was perhaps a bit distracting for overtaking vehicles, but I have seen drivers blow by me flapping away on their cell phones and a 2 x 4 probably wouldn't get their attention. My average ride is around 90 minutes so battery life would in general not be an issue. I do longer rides weekly so will have to deal with battery consumption as It occurs. Install a light as a good safety investment, this light is my choice.
Update 24 Jun 17;. I will not ride without this little fellow blinking at my stern. I take longer rides on occasion and find it has the on or near stated 5 hour life at slow flshing. It has run out of juice a couple times towards the end of the ride. My simple solution; purchase a second! Now have a fresf charged unit in my under saddle tool bag and a spare mount and cable. I do not ride without this little light. ESSENTIAL Cycling equipment just as important as a helmet.