My own personal opinion I'd still go with the full on light, there's a lady that cycles past the end of our road on a regular basis with a "be seen light" and one day when I went to pull out she was just at the wrong angle and maybe at that dusk time of day when a "be seen light" gets lost with the last of the days light and I almost didn't see her .... I stopped just at the last second but it made me realise how vulnerable we are to the surrounding conditions.

If she had of had a more powerful light I'm sure I would have seen her much earlier and not started to go in the 1st place.