Magicshine MJ-818 HA-III SSC 42180U 3W 3-Mode LED Bike Tail Light Set (4*18650 included)

Pros: Links in well to the front MagicShine light. I run it with a splitter off the same battery. Initially wondered about the waterproofness, but its proved me wrong. No issues after 3 months riding, during a wet New Zealand winter! I generally run this and the front light 2hours between charges (front on strobe). It may run longer but don't want to risk it. Very bright - have had the odd complaint from motorists.

Cons: Doesn't seem to have a rapid continuous blink - alternates between very quick blink and slower blink. personal opinion is the fast strobe light / rapid blink is always the way to go for cyclists down here. The turn to change setting function does make it a little hard to start/stop.

Other: It's made me more noticeable, easy to use with the front magicshine light. And seems to make most drivers give me more room. Have recommended to others here, who are SIMILARLY IMPRESSED.

Pros: Very bright and easy to use. Simply turn the casing for different modes. Holds well with two different size rubbers. Solid and waterproof.

Cons: Only one thougt: As most saddle poles are off-vertical, some sort of wedge should be built into the mount. Else most energy points to the road.

Other: Nice backlight in good Magicshine quality. Easy to use and proud to have.

Pros: Audi like build quality Swiss Army Knife like usefulness Uma Thurman like aesthetics (ok mybe not quite there but good) Just a great tail light - I think that the entire cycling industry has forgotten the need to take tail lights seriously, this is a great tails tail light and has answered all of the gripes I've had with the last 45261 different tail lights I've used Very bright no really Very bright As cheap as the production budget of the Blair Witch Project

Cons: None, unless you're trying to get away from a T-Rex, he'll definitely see you with this

Other: Get one, and get one to give as a Christmas present to someone who doesn't even ride a bike This tail light is so good it is the reason to buy a bike and go riding in traffic

Pros: This tail light is VERY bright, I never seen anything like that.
The design is very good.
The crown switch works well with winter gloves.
Runtime is perfect for commuting and night rides about 3-5 hours.

Cons: Probably not waterproof !
I use it under rain and it goes off, it works again after a long drying.
(I do not try the battery waterproof ability, because I put it in a saddle bag.)
No angle setup, the angle of the light beam depend of your seatpost tube !
Sometimes you have to turn and turn again the crown before it switch the mode, could be a bit irritating.
The wire between the light and the battery is ugly and you have to fix it on the bike with some not furnished velcro straps.

Other: A very good tail light, cheap a poweful.
The sealing and the angle setup are the only cloud on the horizon.

Pros: Extremely powerfull, it will protect you from cars that will have to avoid you because light is exageratly powerfull. It is a unique bike tail light set. I've never something like that!

Cons: Not as much practical as it could be. It is quite easily removed so that you have to remove it every time you park the bike in order not to be stolen which not the most practical way you could expect for a bike light. In fact, it is not so easily removed and you loos quite some time to do that because you have to remove two things the light and the battery. You have to be carefull with the cable that is quite fragile.

Other: It is though interesteing, I don't regrt buying it but it fall down and start failing. I va to buy a new one right now. I was expecting that it could exist a new model wich woudl be bundled with the battery but it still does not exist or is not sold by delaextreme.

Pros: The brightest rear light I have ever seen, bar none! Build quality seems excellent as well, I bought this last October and used it through the winter in all conditions, rain, ice, road salt, etc. without the slightest issue. It also works really well with the Magicshine front light: like others I bought the Y-splitter and extension cables so I could run the two off one battery. As with their front lights the O-ring mounting sysytem is pure genius: total simplicity for removing and replacing.

Cons: The switch mechanism is fiddly to use and easy to turn past the point you were intending to get to, eg. switching it on again when you meant to switch off. The battery is not protected from water at all: I keep it in a saddle bag because of this. There is no flashing option that is legal in the UK, i.e. a 1-4Hz constant flash: after a minute it starts altering the rate/pattern etc. which is not allowed by law here. (I use it on steady setting.)

Other: An outstandling bright, good value, practical and well made rear bike light!

Pros: Super bright. Day visible. Works great with the front light (808E is a good one) with a Y cable. I got the updated battery with a rubbery waterproof cover (it also came in the new different box). Overall very impressed with quality and function.

Cons: Needs to be angled up if attached to a seatpost (part of the reason why I installed mine on the helmet). That's about it.

Other: Very cheap life insurance. If you ride with your child on your bike (and you don't live in Holland), then GET THIS LIGHT. I have front and rear flashing during the day. Why not?

Pros: 1. Very bright.
2. 3 Modes, just about right!
3. A selected mode in combination of its brightness can be found that works well at any time of the day or night.

Cons: 1. Poor and very limited method to mount on bicycle.
2. The plastic part on the back of the light is held with a single screw and seems inadequate in keeping the grommet around the wire in place. This makes it almost certainly less that water tight.
3. There is nothing around the wire on the back of the light to prevent tight bends, which causes the insulating material to crack and finally, the wires to short out.
4. The quality of wires used is very poor and they fail on virtually each end within a year:
a. At the back of the light
b. At the connector ends (battery as well as the light)
c. Within the battery pack itself.
d. Poor quality soldering throughout

Other: At the time when I purchased it, this was the brightest rear light I could find for bikes. But now there are several more options that seem more convenient, given the caveats listed above. Some of them are not too much more money.
I have many bikes and in any given season, depending on the needs of the day, I ride about 3 of them. I would buy one for each bike and go for a permanent mounting, if DX improves the quality.

Pros: A extremely bright tail light. This light can been seen clearly in a bright sunny day. Easy to use, well built (except the rotary switch). A full charge of the battery can powered the tail light for more than 12 hours (my longest ride with the tail light on).

Cons: The rotary switch is the source of great concern for me. The rotary switch on my first unit fails after a year. The second unit fails 2 months after use. (DX send my a replacement without hassle since it is still under warranty)

Other: Knowing the rotary switch is a problem, I turn it on and off by plugging/unplugging it from the battery.