Garmin works fairly well with lights. but lights will bring out the most glitches. they disconnect or if you forget one it can cause it not to find it again (like headlights) and you always charge them together as the garmin can turn on the headlight when you charge the garmin but then not turn it off. but garmin will tell you when the battery is low too.
this is where e bikes shine with built in lighting that turns on and off with the bike.