The ones that I've seen and used have been nice and bright. I had a pair that came from Able-2/ShoMe mounted in common PAR36 housing, like used on foglights, etc. Both were red and came with a proper flasher which I liked because you could get multiple flash patterns. Midland Sheriff's Office has used the same lights in blue on the rear decks of their cruisers for several years and they can be seen for a good distance. Now, both their lights and the pair I had were Generation I LEDs, so I'm sure that the ones available now are brighter. A paramedic friend of mine who lives near El Paso had a pair of PAR-36 Generation III from SpeedTech bumper mounted on his Suburban. And even considering the source, they were quite bright.