Let me start by saying these little blue blinking lights have been sitting on my dashboard for 3 months now, and they're still going strong! The solar charging works surprisingly well - even after leaving my car parked in the shade for a week, the lights kept flashing every night.
The installation couldn't be easier. I just wiped my dashboard clean and stuck them on with the included adhesive. Though fair warning - some users reported the adhesive failing. I'd recommend using 3M Velcro like one reviewer suggested, especially if you park in hot areas.
Now about that blinking pattern... While it does mimic alarm systems, I agree with other users that it could blink faster to look more authentic. Currently it blinks about once every 2 seconds, where most real alarms blink faster. But honestly? At night from a distance, it's convincing enough.
Here's where these really shine (pun intended): They create visible deterrence without wiring or batteries. I've noticed people walking past my car at night actually pause when they see the flashing light - mission accomplished! For $10-15, that's pretty good value.
Some drawbacks: The plastic casing feels cheap (because it is), and professional thieves will probably see through this immediately. But for deterring opportunistic crimes? Works great. After 6 months of use including freezing winters and scorching summers, mine are still functional.
Pro tip: If you want them to flash during daytime too, just cover half the solar panel with electrical tape as mentioned in the product details.