It may be totally unrelated to the RLU, but after 3 bulbs I gave up. Maybe someday I'll get back to it. As a rule, I try to avoid after dark driving, so not much of an issue right now.I have the H4 bulb in my 77 GL1000.
Back in the day, (late 70's) I was living in New Mexico, with lots of wide open spaces. I had 2 pair of driving lights that definitely turned night to day! Wasn't thinking about the charging capabilities, just knew that horn and turn signals were not an option when they were on.... driving lights to mount that will turn night into day when I have the high-beam on. I just worry about the stator output.