Summary: Worked well with some issues, lasted 3 years.

No idea what happened, but I had been leaving review updates, and they are all gone now. I bought this in March 2019, but the lawn mower broke it, so in June of 2019 I bought it again. It stopped working, and in March 2022 the manufacturer sent another receiver (which was very kind), that worked for a while, but has stopped again. The solar panel is very white. Occasionally it works, but in the past two months it's missed more and more cars and now it barely ever goes off.

When I first installed this Htzsafe, I needed to turn up the sensor range, and it was very finicky, but I got it to work, but didn't feel like messing with that again. So I looked on amazon for a well-reviewed (I sorted by reviews) and this driveway alarm is very well-reviewed, but I found another brand that has similar good reviews, but has a toggle switch for the range. We'll see how well it works and how long it lasts. Hopefully, Amazon does not erase my updates on that one. The brand I switched to is: eMACROS Long Range Solar 1/2 mile
The only thing I know so far is that the range is longer (I moved it up the driveway to where this one did not work, so I guess the 1/4 mile and 1/2 mile designations are not totally made up) and it's worked for about 2 hours and 6 passing cars (in and out) without any false alarms. The sensor design was a little different, and the Htzsafe worked so well that I was worried a different sensor design would have issues. But so far they are working the same, just longer range. Oh, Htzsafe does have many more chime options. The eMACROS appears to have chimes dedicated to each channel, and no way to change them, (there are 4 channels) so you have 4 chime options as a result. But maybe I'm missing the setting.

The instructions for this unit are unclear to me, but by using their email tech support, I got my system going. I have two sensors and two receivers. Both receivers (on different floors of my house ) can detect either sensor. The led's behind the power (and control) button are not explained in my instructions, but tech support clarified it for me. (On mine, the green LED seems to indicate that the battery is charged enough - and it seems to go off after awhile - even when the battery is OK).
I have mine set on the highest sensitivity (when off, tap the power button 5 times as stated in the instructions - I activated the button about twice per second 5 times). The furthest receiver is about 3 walls and two floors away from the source - probably 140 feet, and it seems to work reliably.

I'll offer the following:
a) after movement is detected it can be up to 10 seconds before the receivers go off.
b) turning if off (three presses of the button) turns on a red LED that shows it is going through the shutdown process - it can take about a minute before the red light goes off permanently. And once, after turning off, it sent one final detection signal out about a minute later - with a red blink - and then finally stayed off.
c) two presses of the button (when it is on) is supposed to activate the sensor - but it does not always do so. But it does seem to reliably detect movement.
d) There is a beep to inform you that the button is pressed sometimes. There are other beeps (a long one when shutdown starts - sometimes). I did not find it worked the same each time - if you knew what was really going on, it might be helpful.
e) my system has only been operating about a day - so I have no idea if it will last or not.
f) there us a youtube video - it mostly repeats the manual but it does help with how fast to press, etc. search" HTZSAFE T704&805A

Good luck - I did not find ANY systems for sale without some reasonable complaints - and I worried about this one but - so far, so good. Be sure to contact tech support if you are having problems - they seem very helpful.

works great my dogs now even know what it means when the alert sound goes off

The first one worked great until it got water inside. They are cheap enough I decided I could afford to replace it every few years. The new sensor has a substantial rubber seal. Hopefully that corrects the water infiltration issue that so many people have had.

I have had this for almost a week now, and so far it works well enough. The sensor picks up vehicles nicely, but people walking past must be closer to the sensor than I had hoped for. It seems to only pick them up at half the range. (I had my son walk past the sensor several times at various distances from it to test it.) I have also had one incident where it went off one day for seemingly no reason. (I even watched my video surveillance to be sure I didn't miss anything...) Ghost car maybe? LOL! But only the one time so far. My receiver is not too far away from the sensor so I can not verify the quarter mile range, but it works great where I have them installed. I just now ordered one for my uncle who lives next door and has a more narrow driveway so it should be perfect for him. As far as the weather proof feature, I haven't had any real adverse weather yet so we shall see. Unless you count hot, humid days as adverse... LOL! I have not "played" with the ring tones either, since the first one it played (classic doorbell sound) was the one I wanted. Overall, so far anyways, I like it.