This is a meaty beast, and pretty heavy. However, the USB charging (at my desk during the day) and it's ability to light up an unlit towpath really well are amazing. It has high beam and low beam, like a car or motorbike headlight. The flashing (strobe) effect is very good, with the outside staying on, while the inside pulses, so you don't get any 'off' phases.
The bracket to fix to the handlebars is thankfully very robust (I have had previous, albeit much lighter, Cateye lights which had useless flappy brackets and the light moved about). It would need to be for the weight and bulk of this particular light though.
For battery life and in town, leave it on strobe.
You will need to charge for a full 8 hours before use.