Yes buy a light for sure....my GF and I went out last evening for 28 miles after 5pm and made the mistake of NOT taking our headlights. BIG mistake. Last 30-40 min of the ride were really slow because we couldn't hardly see. We had tail lights so we felt safe from being hit...but I had to go slow because we couldn't see...and were being VERY aware of cars turning out of roads in front of us at well, knowing they probably couldn't see us.

I'd suggest 800-1000 lumens of light. I have a Light and Motion Urban 800 which is very nice and plenty bright but I also just got this unit off of Amazon for MUCH cheaper and it does a great job: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Honest gripe about this cheaper unit is that the handlebar mount is pretty bulky. I'm using the helmet mount on my handle bars though and it works just fine.