Well, the instructions are for a previous model, or firmware perhaps.
Reading those, and then the reviews apparently referring to those instructions, I was skeptical.

So, this all got hooked up on my desk first, not my car. This is a real review.

Things I found:

Instruction sheet (and several reviews) says you can only record two streams is incorrect. When you plug in the back camera, all three streams record, every time. There isn't even a way to turn one off, other than unplugging the external camera.

Video quality: great on the forward camera. Pretty good on the interior camera. Not great on the external rear facing camera.
It's OK for video evidence of that guy hitting your back bumper, while the front cam shows a red light, though.

Options: Motion trigger. This works, for a while, then it doesn't. It records several clips then the option just turns itself off. And the recording stops too. So don't use that. It's a bad idea anyway, at a quiet intersection, nothing moving in front of you, motion detect sees no motion, so no video, and a guy sideswipes you. You'd miss that accident with motion detect because it only watches the front camera.
I tried this with and without the "G-Sensor”, as it appears to be a vibration sensor.

Parking: I kind of made that work, by turning Parking + G-Sensor + motion, and it recorded a locked clip when I tapped it with my hand. I had a couple successful clips.
I didn't pursue this very far, because the instructions say to never leave Parking (or motion!) turned on for driving, you have to set both manually EVERY time you park on two different config screens. I thought this mode would just be automatic when you parked. This doesn't interest me at all. I tried it anyway, and ran into the same problem as before. The Motion detect just goes away after a while, and the recording stops completely.

Phone App: For bandwidth reasons, to watch the video on your phone, this operates on WiFi, not bluetooth. Which means connecting your phone to a local hotspot the camera creates, every time. Then you have no internet, because it's a hotspot without internet, right? It's very annoying. I'd rather just have the files and utilities available on the app, download the videos to play them, and use BLUETOOTH instead. That's not how this works though.
The camera continues working while streaming to your cell phone. But the camera is stuck on the "WIFI" screen, you can't exit or use any functions or buttons while connected to your phone.

The APP Viidure, works OK, and there are a few camera settings in there. Not all, just a few. Plus you can download your video clips into your phone.
(HINT: Its much faster to just put the card in your computer with a card reader)

Through 2 days of testing, I didn't experience any lockups while in WiFi mode, or during testing the camera.

For what you get, it will do the job. You don't need to connect your phone all that often, or use motion, or parking modes. Then you have a 3 camera 1080/720/720 system for $89 at the time of this review. That's OK, there's some value there, especially an uber driver situation when you need a camera on the back seat. I’d like a 3.5 star rating for this one.

It's not hard to notice for $20 to $40 more there are 4k/2.5k systems with much higher res cameras, that may have better functionality. I don’t have one to compare, but just saying it's worth thinking about.

This simple camera setup is great to get video for your vehicle on a budget. The front / interior camera plugs directly in to your lighter wiring. There is a separate (optional) rear camera with wiring that ties in to the front and plugs in, but the length of wiring works for compact cars or small sedans, certainly not SUVs or larger cars. Plan accordingly.

The video is standard VGA, nothing too fancy but should be enough for insurance if heaven forbid you get into an accident.

As far as generic dashcams go, this checks all the right boxes as long as you're not expecting stellar video quality. With 1080p front, 720p rear/ internal camera, coupled with a cheaper sensor, the video footage is acceptable. In good lighting conditions the front camera can pick up license plates to close cars easily enough, as can the rear camera for cars directly behind you. Night footage isn't the best, as to be expected, but I believe it would certainly help in a situation should an "incident" occur where you needed to use the footage. The internal camera, being the lowest resolution, works fine and is lighted in the dark.

The menu system / buttons aren't the most intuitive, with a lot fiddling needed if you don't have the manual in front of you. However, once you've got the settings as you'd like them, you don't have to play around with them. I like that it includes a 64GB card so you can get going right away. It will quickly fill, but as it's loop recording that isn't really an issue.

Overall, it's an average quality dashcam when you factor in the cost.

The TOPGOOSE 3 Channel Dash Cam offers comprehensive protection with its triple channel system, capturing video from the front, rear, and inside of your car simultaneously. With a 170° wide-angle front camera, a 160° in-car camera, and a 160° rear camera, it ensures all-round surveillance to retain evidence in unexpected situations like collisions.

Featuring high-performance Novatek chipset and Sony Sensor, this dash cam delivers smooth 1080P front video, along with 720P cabin inside video and 720P rear video. The IPS screen provides live-time video feedback, making it ideal for Uber, Lyft, Taxi, rideshare drivers, and anyone who wants to monitor their surroundings.

You can easily control the dash cam using the Viidure app on your smartphone via WiFi connectivity. The app allows you to view, playback, manage, download, and edit videos directly from your IOS or Android devices. With super night vision and parking monitor functions, it ensures clear video and images even in dark conditions and offers 24-hour parking mode recording.

Equipped with a Gravity-Shock Sensor, the dash cam automatically locks footage as evidence in the event of a collision or bump. The loop recording function overwrites the oldest unprotected files when the TF card is full, ensuring continuous recording. The compact design of the dash cam is easy to install and won't obstruct your view while driving.

With a one-year warranty and 24/7 technical support, TOPGOOSE provides worry-free after-sales service. Plus, it comes with a full refund within 30 days, ensuring customer satisfaction and peace of mind. Overall this is a great unit that works well and has great features and good support from the company. A great product that works well and does everything it’s supposed to do. :)

I have owned the K&F Concept Dual for more than 4 months now and would like to briefly share my experience.
First of all, I am still convinced of the dashcam! Overall, it delivers a good image, even very good images during the day, although it must of course be said that this model also does not have autofocus and therefore does not focus infinitely. Unfortunately, you can no longer read license plates or signs at night, but almost all dash cams in this price range have this problem. If an accident occurs, the video can also be used to reconstruct the accident at night.
I only use the front camera. It's a shame that you can use both cameras at the same time, but only in Full HD mode. For example, if you want to operate the front camera at 60 FPS, you inevitably have to leave the rear camera switched off. The processor is probably unable to process the data. If you set a resolution higher than Full HD, I personally don't see any advantage in the image.

The motion mode works very well. I've had to brake hard several times and the camera reliably saved the current video. If you want, you can save the video yourself at the touch of a button.

We bought this camera for security at our apartment. This has been the best buy we have made. I can check my front door when someone comes on our porch plus I can keep an eye on my car. The picture quality has been great day and night. Plus it's solar-powered so no worries about the battery. And the memory cards make it easy to keep events for later viewing. I would say buy this one for easy set up to the phone and for easy to put up. Worth the money!

I bought the camera to monitor the outside area in front of my front door and am delighted with the quality of the camera.
The installation went smoothly and the area can now be easily viewed via the app. The camera is charged via the supplied solar panel, so no power connection is required! Perfect. I can recommend the camera unreservedly.

I put this camera on the front door. It's very easy install and setup. Video quality looks great. Love that it’s wireless and no longer have a 9 foot cable hanging on my wall. App is pretty intuitive.