And I was right - 3.5 weeks, yes, 3.5 weeks, from fully charged to low battery shutdown. In it's defence, this was the first few weeks filled with novelty, checking in every now and then on the live view. During this first charge period, I had it set to a high sensitivity of human detection in a defined zone covering a third of the camera's field of view, within private property. It did sometimes capture people walking by on the very fringes of the zone however, so I've since reduced the zone further to stop this. It's not much of a complaint however, as I took 180 days as a pinch of salt right from the start, and fully expected to be charging it with shorter intervals. Charging, by the way, is a breeze; releasing the unit from it's mounting bracket with the supplied pin (think a smartphone SIM port release pin on a slightly larger scale) and sticking it on overnight, or until the circular status light turns blue. The release pin presents well (in the form of the Eufy logo) and is magnetised, so you can stick it on your fridge and avoid losing it - nice touch.
The unit itself feels well made and has a decent weight behind it (surprisingly so). Was super easy to install. Night vision is better than I expected, although I wouldn't say the quality (day or night) is "2K", subjectively speaking, but it's still admirably good and satisfactory for a doorbell camera.
One drawback from being battery operated and thus not constantly recording is that the motion detection takes a second or two to activate. Might not sound like much but it's enough for someone walking onto your property to have made it a good portion of the way to your door by the time it kicks in (unless you live in a mansion with a driveway a mile long). Still - it's a limitation of any type of camera operating on this power-saving, battery-powered basis, and you'd need to invest hundreds or more in a proper CCTV system to combat that. I say "proper" as if this isn't a proper system, and therein, I suppose, lies the gist of it. As a reasonably priced pretender, however, it is a very good effort and better than other doorbell cameras I have seen, not least because of the lack of subscription fees; in a world where everything seems to be subscription-based, we liked that there are none with this system.
The lag time between a motion detection event occurring and the notification on my phone is a little hit and miss - sometimes within a couple of seconds, sometimes (tens of) minutes after the event. This only seems to be an issue with my relatively old (2017) Android phone, while my partners new (2021) iPhone is practically instantaneous with all notifications. I'm sure there must be some sort of power-saving Android function that I'm missing somewhere, as I do have notification lag with other apps too.
On the whole, I'm pleased we bought this as it provides peace of mind that nobody is skulking about our front door at night. The presence of a camera doorbell isn't much of a deterrent, but it should serve as part of a broader mosaic of surveillance and anti-theft measures you have in place, along with the added convenience it affords in relation to missed deliveries or being out of earshot of the doorbell sounder.