the cleanest way is thru your frame . requires drilling 1/32" hole in your fork's head tube, along with another in the seat post. works like a charm for me... never have to worry about lights nemore.

Anyone already Bought one of these ? SON Rear Light does it stay on when you stop?

what are the connectors? Do they interfere with the flat strip rack mount on a Tubus Rack?

Looks tidy.
Apparently is does stay on:
Integrated standlight capacitor

I have the B&M Lumotec IQ Cyo T Senso Plus front light and it comes with the wire you need to connect the rear light. I brought the B&M toplight line plus rear and it works a treat, The rear light will stay on for about 4 minutes when u stop the light bolts to my rear rack so its a solid fit, And unless you have the right size spanner on you its hard to steal...but its a solid light only no flash option.

So far , I have 3 bikes with rack mounted B&M taillights, I rigged up the one on my Bike friday to use 2 old mudguard struts

off a scrapped Zefal Mudguard to mount a Toplight Line Plus tail light right behind it's rear water Bottle

a Placement inspired by where the same taillight went, on my Brompton..

I like the B&M and also the Spanninga Pixeo.