I'm really surprised to see so many negative reviews, especially regarding customer service. I have been a customer of Kuna for several years, I originally purchased two contemporary security lights and while these may not be the best bang for your buck or super-reliable connection-wise, they are great for those who are renting and aren't allowed to make major modifications, such as drilling in order to pull data and power through walls in order to connect the system. Since these lights wire directly into existing 120V light boxes, it is ideal for this application.
I have since bought a house and brought my two existing cameras with me and purchased an additional flood light security camera for the backyard when I moved in March. I will say, I had two returns of the floodlights; the first problem being the light stopped seeing WiFi. I sent it back and the replacement's motion sensor didn't work. Third time is a charm, and this one has been working perfectly ever since.
I've never had any major issues with the two original security lights I purchased. Kuna's support has always been responsive and reasonable. I rarely ever have any problems getting a signal to the cameras, and they are a considerable distance farther away from my router in the home I moved to vs. the tiny apartment I moved from. Perhaps those complaining about connection issues have a higher level of interference or some other mitigating factor. WiFi can be a tricky thing, and it can be the trade-off vs. hard-wired camera systems, which are generally much more reliable, but harder to wire and connect.
Regarding late notifications. Early on, I seem to remember a handful of times where this happened, but generally speaking, I haven't had any issue receiving notifications within seconds of detection.
Bottom Line: Yes, I would recommend this to a friend