Very good quality of the product, especially considering the cost (comparing to the comparable ones from other manufacturers).
Light is extremely bright. Normally I'm using lowest or the 50% setting. Higher settings are used only on very difficult terrain or just for the fun of them ;).
Amazingly the battery life is quite good when the light is used on the lower end of power scale.
Build is sturdy and quite elegant. Mounts are solid, o-rings and velcro straps are working great.
For now there are only three small problems with the light on everyday use:
1. The buttons on the light (power up/down) are a bit difficult to use when driving, especially when using glove. The o-ring is a bit flexible, which is good, but it makes changing power level a bit tricky.
2. When connected to the battery, the signaling diode on the back of the light is always on. I've not found any measurable impact of this on the battery life, the power of this diode must be minute comparing to the four ones on the front, but it's a bit annoying.
3. The last one is not a problem per se, but something of a feature. The cone of the light is quite wide. It's great when driving because you can clearly see not only what's directly before you, but also what's on the sides. On the road it can blind the incoming traffic, so one must be careful with the power and the level on which the light shines.
Overall it's great product.
As an anecdote... In two weeks I'm using this light I was stopped on two separate occasions by people asking me about the what kind of light I was using. They were amazed by the brightness of it. I was amazed also... on both occasions the light was on its lowest setting ;)