Hearing all the good advice, I picked one up on ebay super bright and about half the width and depth of yours I love the mounting position as it is as high as possible, and neat, and my narrower version leaves a lot of real estate for go pro.
But agree with hood on its obscured at the one time when you need it most, in dull dreary wet conditions catch 22.
Could you just use self-adhesive, weatherproof red LED tape? You could put that almost anywhere in any length, and with a black PCB it'd look reasonably unobtrusive. May have a play with this idea over winter :)
Interesting. I bought one (same as #7) to fit but never yet did the deed because it interferes with camera mounting of both GoPros (not a huge issue because I fit several of these elsewhere) and my Canon DSLR which I sometimes use... typing this it strikes me a Velcro solution might work, since when I use the big cam there's rarely any following traffic, and if there is the DSLR is pointing at it.
Velcro : maybe a second strip on the rear of the ReBag.
The PGM offering I will look at as their engineering I have seen (DS CRA) looks nice, if twice the price.
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