Originally Posted by
ThermionicScott
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Thanks for the affirmation! Once replies started rolling in, I worried that my question was obvious to everyone else, and a waste of their time. I was sorry to hear about your Cygolites, mine has been completely reliable, but I've had other lights that just died out of the blue. Frustrating and disconcerting.
Most of my bike taillight experience is from bike touring. I have settled on one Planet Bike Superflash and also a Planet Bike Superflash 65. Both are AAA models. My last bike tour was a rainy five weeks in Candian Maritimes, and I never had a water ingress problem.
I had one light (a cheap brand light) die on my Iceland bike tour, corrosion from too much water getting into the electronics from too much rain.
The Superflash has a very tight beam, so if aimed well it should be very visible from directly astern, but only minimal light to the sides, up or down. I mostly use that on days I plan to be on long straight roads. The Superflash 65 has a much broader beam in all directions, I use that on winding up and down roads because of the broader beam in all directions.
If you choose AAA batteries, I use NiMH rechargeable batteries but I would expect that you want the greater capacity of disposables if you are using AAA batteries that need a long life. Touring, I charge up the AAA batteries once a week whether they need it or not just to make sure they stay bright.
It was mentioned above the concern about two lights being mistaken as a car with two taillights. Put one higher than the other to avoid the potential for that confusion.