For a long time, I've lived and worked around a small municipality that regularly issued around 1,000 tickets/per resident/per year. We have been #1 in the state for citations per residents issued by a long, long margin. I've had a radar detector continuously sitting on my dash for more than a couple decades.
Good detectors cost more than $100. There is little difference between low end detectors. If you're looking to spend under $100 bill know up front that you are getting what you paid for. Frankly, cheap detectors are not worth owning. Cheap detectors lump K band and Ka band together.
Highest rated radar detector for years was the Escort 8500 X50 (discontinued). Since replaced by the Escort X80.
https://www.stealthveil.com/best-radar-detector-reviews-2018-top-rated-radar-detectors We have old model Escort X50 in all of the family vehicles.
Escort allows you to turn bands off/on and displays band being detected on the screen.
Leave POP off, POP is known to give faulty speed readings and there are only a couple small areas in the country that use POP radar. Turn X band off, X band is from the 1940's. Very few agencies run antiquated X band and it produces false alerts in urban areas.
Ka band is always an officer collecting revenue. Every time. There are no false Ka readings.Laser- hope the officer lights someone up in front of you.
K band- K band could be an officer or it could be a false alarm. If you put competing radar detector brands on a roadway, Cobra & Escort will detect each other and give false K band alarms.
Run "Highway" mode all of the time.
In wide open areas, a good detector will pick up a radar up to seven miles away. So far away that you'll think it's acting up and giving a false reading. In tighter areas with terrain, they give you time but the distance is significantly reduced.
When you get pulled over with a detector, leave it on the dash. Police officers don't care any more or less if it's on the dash. Put it under the seat and you are a deceptive creep. Leave it and let it flash during the stop but hit the mute button.
In my lifetime, I've been pulled over three times without the use of radar/laser that I'm aware of. In each of those cases, I would have been cited if there wasn't a radar detector sitting quietly on the dash. One claimed to visually estimate my speed. One claimed to "pace" me after seeing the detector. One I mistook for a road rage aggressor rather than an officer. In all three of these cases, there wasn't cause for the original traffic stop.
IMHO laser should not be legal for traffic enforcement. If I was to point a laser at motorists I'd be charged. I don't want a laser pointed at my face for any reason. A hundred dollar citation shouldn't be worth my eye sight.
Around here, friends and family of police officers get a bear sticker to display in their rear window. These are color coded stickers used to aid in selective enforcement. While I am not anti cop, this rubs me the wrong way.
It's a Washington state thing.