I suspect they're decent as "be seen" lights. I base that on getting a front Flea shortly before DST started. It's aggravating on flash, because you find out where all the reflective surfaces are within a block. Doesn't do much of a job of lighting up the road surface in suburbs with solid "on", though.

I'm curious what sort of close calls the OP has had. I run 2-3 blinkies in back, and don't have problems. PB Superflash is highly visible (until it gets wet). Anything on the front, from a be-seen to 15W halogen (or equivalent) seems to alert oncoming or waiting traffic. I usually have fewer problems at night than I do during the day!