OK, don't know anything about mini-cams, helmet mounts, power supplies, rear view vs. forward view, or adaptability to light conditions, but I do know myself. If I started fiddling with cameras during my rides, one of two things is going to happen--I'll cut into my ride time while futzing with them, or I'll get so distracted trying to keep them working while I'm riding that I'll end up plowing into the back end of a car.
More power to you who are keeping them working, but I'll take a hard pass.