I've used the FL220 when I was a cop in the USAF. It was great to have for the portability of swapping from one vehicle to another and was effective enough
IMO, especially before the dawn of LEDs. The stealthiness/out of the way factor was nice. I'd seen folks just wrap the cord up and fold it into the visor so when they dropped it down, all they had to do was plug it up. Seen other folks route the cord along the A post, under the dash and to the cigar plug, so all they had to do was flip the switch. Two people ran it on my
FD before we went paid and for the short distance they had to respond to the station, they'd get most traffic to yield to them.
As with the majority of dashlights at night, you will have to worry about flashback. As with any visor light, be sure when you flip down the visor, the light is perpindicular and not pointing to the sky or ground and it should be seen, provided you don't have any horrible tint impeding it.
Another good thing is that due to their age, you can usually find them for good prices.
