I hear ya. I don't find I need 600 lumens to be safe while commuting, but I don't think it is overkill either. A 120l I would find unsafe though. I think a couple 200l's is a pretty good combo, but for the price of 2 of those you can probably just get a 600l so that makes more sense. I was riding around the other night semi-ninja style with about 100 lumens and I didn't die either, but I certainly couldn't ride as fast as I would with 500 lumens or more and I wasn't able to see the road surface as well as I would like. I set my Wilma to 12% power (~100 lumens) just to see what it was like and it was doable, but when cars came at me it made it unsafe as 100 lumens wasn't enough for me to see the road safely. 400-500 lumens seems to me like a good amount to safely commute, but more certainly helps in some situations.