I really like the lights Serfas puts out. They don't have super long run times, but they are USB rechargeable so I think they are great for commuting. I use the Serfas USL-5 in flash mode on the handlebars and a Serfas TSL-500+ on my helmet in constant on mode. For tail lights I have been using a combination of the Serfas USL-TL60 on my saddle bag/backpack and a Serfas UTL-6 Thunderbolt on the seat post when not using a saddlebag. I have been wanting to put a tail light on my helmet for some time and was searching high and low for a good tail light that I could easily mount on my helmet. Then, I realized I could put one of my Serfas UTL-6 Thunderbolts on my helmet. I love it! It is super secure, the light is very bright, and it is not directional so you can easily see the light even if you are night directly in the line of fire. The only issue is I have to remove it to charge it, but it only takes me about 10 seconds to remove it and about 30 seconds to put it back on.

Note: I did get longer straps for the light. Serfas sent them to me at no charge.