This is actually the one I use. I ride at night for fun during the summer, it's not so bloody hot. Four miles of the ride are in the country, no lights but mine, and it gets me by just fine at around 15 mph. Nice flood and spot, I can see about 8 seconds ahead, that's about 176 feet, which is plenty, and lights up signs and barriers from half a mile. If you're looking for a tail light that's not horribly expensive, I suggest the Radbot 1000. It's brighter than the Planet Bike Super Flash, and can be had from $20-25.