We liked the single Asteri 3 light a lot when we tested it before Christmas. The Asteri 6 combines two 3w headlights, but while the 6’s brightness is good and we got the three hours' running time claimed on full power, we didn’t like it as much as its little brother.
It charges quickly, in just a couple of hours or so, the battery is small, neat and straps well to the bike, and the lights survived some heavy, prolonged downpours.
But the system isn't bright enough for proper off-road use, the cable is too long – a good thing if one of the lights is mounted on your helmet, but it gets in the way when you're running the lamps on your bars – and the plastic head units don't feel as reassuringly solid as the metal Asteri 3.
We had a couple sets on test, and one of our reviewers reported that road vibrations caused the rubber handlebar mounts to swivel around the bars, to the extent that they had to be tilted back down every five minutes or so to avoid blinding oncoming traffic. Other users had no such problem, so that could be down to bar diameter or the particularly rigid alloy frame that the lights were being used on.
One final issue is that, while the cable is long enough to mount one of the head units on your helmet, you cannot simultaneously run the second lamp on your bars.
If you're after a bright light for road use you could certainly do worse, and there are deﬁnite advantages to running a twin headlight – you can run one on constant and one ﬂashing, or illuminate different parts of the road.
However, at more than twice the price of the Asteri 3 this doesn’t offer you enough for your money. We think you’d be better off running two self-contained single headlights instead.