Lumen output is only one thing to consider. Apparent brightness also depends on the beam angle that the output is concentrated into. And a front light us only effective when riding against traffic. If traffic is approaching from the back then a bright front light is useless. That said - I've actually been very impressed with the performance of the Blackburn VOYAGER 2.0 FRONT LED light. In fact I run with two of those in flashing mode rather than a 700 lumen light also on the bike simply because run-times are better and I can't see any effective difference in the daytime. At $20 they're under-rated. They output a narrow beam that doesn't light the road effectively at night but will reach two blocks ahead and illuminate street signs. And daytime visibility is EXCELLENT!