I'm wondering about the added value of a dash LED if you already have a windshield headliner device. The latter only duplicates more or less the axis and footprint of the former.
From what you describe (crossing a busy road), what you need is intersection warning, so I would suggest, if you don't want to bother with wiring and stuff, that you go for a LED beacon, which at least will provide some 180 to 360° visibility. Or a mini LED bar at best.
The interior lightbar is green (for EMS
). The dashlight would be blue (for Fire).
As far as which one, that is more your personal preference. As far as off axis goes, the avenger would be better than the super slimlighter. I generally would go with a linear style light to the front and TIR
style lights to the rear. Having said that, there are some TIR
style light that do have very good off axis and can be used to the front, it's just that the super slimlighter isn't one of them.
I would also consider the Tomar 200S (normal or high power) for another linear option. For TIR
style options the Sound Off UltraLite 4 or the Predator II have great off axis lighting.
Hope this helps. Let me know if you have any questions.