K40 RLS2 Radar Detector Review

Chris Tonn
by Chris Tonn
k40 rls2 radar detector review

I’ll admit it. I haven’t used a radar detector in years. My typical method of avoiding tickets has relied on the (patent pending) Spousal Alert System, in which the wife screams at me if the car is going too quickly in proximity to one of Ohio’s finest.

Problem is, 10 years in, I have yet to find the mute button.

Plus, she doesn’t drink coffee, so the Spousal Alert System has some glitches on drives longer than four hours. A planned family reunion in northern Wisconsin, 10-plus hours from home, reminded me that an alternative was needed. Thankfully, the kind folks from K40 Electronics offered their new RLS2 radar/laser detector for review. I’m pretty sure it already saved me from a ticket or two. With an MSRP right around $400, it is priced in the ballpark of the major players in the market.

For years, the big selling point for K40 detectors has been their “Drive Ticket-Free” guarantee. They will pay your speeding ticket if you are using their detectors. I didn’t wish to test this particular perk, so I paid more attention to the other features.

Having not used a real radar in a decade or more, the GPS is new to me. If I had a long commute, this would be quite useful. It allows the user to “mark” a location for speed traps or other locations that typically would be a hazard to a speeding driver. Upon approaching the location again, the RLS2 will alert the driver, whether or not radar/laser is present.

Another cool facet is the speed monitor, which easily replaces a screaming spouse. Set a “max” speed, and the RLS2 will alert when the car exceeds it — great if you want to hit a high score, or simply if you’ve got a long day of driving through the Kentucky hills and you accidentally hit 110 mph in your minivan on a downslope.

I particularly love the Quiet Ride. This silences everything below the speed of your choosing. When I was commuting to college back in the late 1990s, I got sick of the cheapie Cobra detector blaring when I was crawling in 20 mph traffic. I simply didn’t care, so I’d shut the unit off and forget about it until traffic opened back up again. When I’m commuting with the RLS2, I set the Quiet Ride at 55 mph, and I don’t worry about it.

No, I wasn’t going to do a Youtube “unboxing” video.

When I opened the box initially, there were a couple of power cords, a windshield mount and suction cups, and the surprisingly lightweight RLS2 detector itself. I suppose I expected something a bit more substantial feeling, though it doesn’t feel cheap. Good thing it’s light, as a heavier unit would be pulling down on the windshield mounts, eventually falling off. I’d have preferred a visor mount, as I would rather have the detector out of my immediate field of vision, but the RLS2 works best as close to the glass as possible.

There are aftermarket mounts available, as it turns out. BlendMount offers options for the most popular detectors and for most cars on the market. It looks like the mount for my Chrysler van runs around $90 — ouch. But it should minimize hassles, as well as my field-of-view concern.

K40 suggests all new radar users contact their toll-free tech support line, even before purchase, to ensure the right unit is acquired. After receiving the detector, another call is advised while parked in the car to allow the consultant to work with you to fine-tune the settings to your typical driving style and roads.

Upon receiving my test unit, I called and spoke to Brian, who asked:

  • What I was driving;
  • What type of driving I do – highway, city, mix;
  • My typical driving speed;
  • My location — though if I recall, he deduced it from my area code.

He told me the out-of-the-box settings are just about right for me, though he did have me tweak the Quiet Ride setting. Easy enough — and as I mentioned earlier, I played with that setting a good bit.

I’ve been using the RLS2 for about a month, including the long trip to the land of great cheese and beer. I was alerted to X-, K- and Ka-band radar throughout my trip, and got one hit by laser thanks to the Brown County, Wisconsin sheriff’s deputy hiding on an overpass. It has been helpful, though I do have a couple of qualms about recommending it for everyone.

First, I rather dislike the button placement. This will certainly become less of an issue over time with familiarity, but right now, considering I place the unit rather high on my windshield to minimize forward obstructions, I can’t read the labels on the buttons while in my normal seating position. A low mount position would be completely unreachable, considering the deep dash of my Town and Country. If I need to mute, or adjust the Quiet Ride speed, I’m stabbing away at six buttons hoping I get the correct one. Some other competitive models have controls placed on the front face.

The ideal placement blocks my view a bit.

Secondly, despite K40’s K-band filter theoretically rejecting alerts from collision-avoidance and radar-based cruise systems, I got a bunch of strong K-band alerts in rural areas of eastern Indiana and western Ohio. After a few of these hits, I made note of the cars around me — none were new enough to have these features. I had to mute the unit several times in these areas. After talking with K40, it seems I’ve been alerted by traffic flow sensors, which they haven’t been able to filter out just yet. They tell me that their next generation of revised products should have this filter.

If I were to add a killer feature, I’d love to see the GPS better integrated into more features. I’d especially love to see the RLS2 switch over from highway to city filtering as I approach an urban area, rather than needing to do so manually. I’d often switch, then forget to switch back to highway after passing through.

My time with the RLS2 has been quite educational, and I’m certain I’ll keep popping it up on the windshield as a backup on long trips, but the Spousal Alert System is permanently installed, as she has features no electronics company can replicate.

Join the conversation
5 of 31 comments
  • Speedlaw Speedlaw on Aug 03, 2015

    The vast majority of laser falses are caused by the laser cruise controls of Infiniti, Mazdas, and worst of all Volvos. They are left as default on...so most of the time I look up and see a Q56 coming toward me, or a "oh so safe" Volvo. Some good rules have come up. 1. Eyeballs work best. I had a passenger once who whipped out some surplus Russian Field glasses. Crossing Ohio has never been easier. 2. Use a top notch RD. This alone is worthy of a million click baits, but use a good one. I have worshiped at the altar of Mike V through big box escorts, the Passport, and now V1. 3. The Rabbit is your friend. Let them crest hills, corners, stay back a bit...don't be the moron in the blind spot. 4. Laser is a fair weather threat. No cop uses it when opening the window into freezing air. 5. Laser is also line of sight. You can see them, unlike a gotcha radar, but they compensate by using distance-he'll be on a hill 1000 feet away as you pop up. 6. Know your threats. Soda can sized antenna is KA, tennis ball sized is K. 7. Don't ever rely on a detector...it is a backup, a small change in odds. I won't drive without. 8. A good RD teaches you where they sit, how they act...it isn't a "cop sensor". 9. If you can move your display, do it. 10. Waze is like CB radio. I don't find it really reliable, but it is another data point. Too many false positives. Great otherwise for traffic density, as that isn't user generated in the same way.

    • Slavuta Slavuta on Aug 03, 2015

      Aiming low. I would go this way - each cop car is traceable, dispatchers know where their people are. Get into the trace system, write application to show all cops locations on map. Drive.

  • Fred Fred on Aug 03, 2015

    How does radar detection help with instant on detectors?

    • See 1 previous
    • Delta9A1 Delta9A1 on Aug 04, 2015

      The Escort's and Valentine's do well at picking up instant-on KA over the crest of a hill, etc. as they hit the car ahead of you. As Speedlaw says above, the RD is a back-up, and you should not be in the lead anyway. Wait for the young guy in the red car to whiz by. None of the RCMP or metro police in BC use K-band any more. They run with KA on while opposing traffic, or use laser when static.

  • Lou_BC Lightning Flash? Seriously? I'm shocked. This will generate much static from the usual suspects. Some will get a charge from it. Others a discharge.Resistance is futile? Gotta chant to calm down: Ohmmm Ohmmm Ohmmm
  • Lou_BC "Barra accused the UAW of having no real intent of making a deal with the industry" Seriously? I guess it's so obvious. They just want to sit around basking in your hotness ;)
  • TheEndlessEnigma Where's the Tassos rant?!
  • Urlik The best way to crush F1 politics is to be good. Looking at you Red Bull.
  • Art_Vandelay Good. As an Alfa fan it will be good to have someone on the grid they might actually be capable of beating!