both lights fit tightly into the holders and the quick release fastenings hook around the bike posts solidly although they can be a little fiddly.
The front light has 4 modes
Full power
Half power
Slow flash
and Pulse.(this is a double flash then a long break then double flash again)
With all modes the light has quite a wide spread beyond the central beam.
The full power would be suitable for in town cycling or country roads as long as you're not travelling at high speed and you could even use it off road and not travelling fast. half power would still let every one see where you are.
Both flashing modes are full power but slow enough not to dazzle oncoming drivers.
The rear light has 4 modes as well and all are bright enough for any use.
The lights charge by usb and come with 2 cables.