I'm a fan of Cygolite. For front lights, one on the bar, one on the helmet. I have become a fan of daytime lights, so I like the 650+ for daytime flashing front and 200 lumens for rear flasher. Most single batter lights max out at 1.5 hour of runtime on high. If you like long after dark rides, consider getting a 900 lumen light and running it on medium; you get longer run time. Also two lights for the rear, with different flashing patterns. I aim them at slightly different angles to increase coverage.