THE SOLUTION: you could take a chance on an Amazon review and go for two of
these. They look like jet engines mounted on thye bike; they mount EXTREMELY easily and are VERY adjustable. Also that have a rather strong blue light that focuses in a nice fat circle so with good positioning of two of them you can be very confident while riding in the suburbs where there is some ambient light. They ARE however not for speed demons but who rides reallllllly fast at night anyway?
THE BONUS: They draw more comments from people than anything I've put on my bike. I've had the most fascinating conversations with strangers that started with a question about the lights. There is something about conversations at night with strangers about bikes that has a totally different focus and reward than daytime conversations about biking.