I have been using one Radbot 1000 (set to flash zZz Pop) and one Danger Zone (set to bright/steady) for about a full year now. I have rode in some god-awful thunderstorms, including those that have all of our rivers currently near record flood stage here in Illinois. We don't get the months-long rain that Seattle gets, but when we get it, it is in the violent downpour variety, and these lights pass the test for me. I used 'em this winter in driving slush, temps down close to zero degF, etc. too. No problems with either light, they have both been fully weatherrproof for me.

Each of the lights uses two AAA batteries. I keep a rotation of 8 batteries going - 4 in the two taillights, 4 on the charger or fresh and waiting. Both use the same mounting attachments. Great lights, I love 'em.