I initially bought two to check them out, now I have a total of six.
Because I have been using two SP018, one SP020, and one SP023 for years, for those of you who have older Sricam cameras, you won't be able to monitor all of them from the same app. The old ones with their old app (which is not the best, among other things you can only monitor one camera at a time from your mobile), and the new ones with the new app (which, for me, is much better and you can monitor up to 4 cameras simultaneously from your mobile/tablet, etc.).
The installation is easy (QR code), if for some reason the camera can't read the QR code, simply reset the camera and try again. It happened to me with 2 out of the 6, but now everything is fine.
Very good range, very fast compared to the old ones (I'm referring to PTZ).
If it hasn't been mentioned, in order to avoid hearing the sounds when the cameras start (which wake up the dead), go into the app and update the firmware for each camera. Whether there is or isn't new firmware, they will stop making noise.
The only negative for me is the very narrow field of view (FOV). And precisely because I also have SP018, I confirm what another person mentioned in their review about these specific cameras. Their FOV is significantly narrower. One star deducted for this.
At 27-30 euros each that I bought them for, they are definitely worth the money and more.
I will update the review in a few months to test reliability first, how they work with SD cards, etc.
UPDATE 5/1/2024: For a while now, I have been using Transcend 300s microSDXC 128GB Class 10 U3 V30 A1 UHS-I on all 6 cameras. Absolutely no problems, they record in FHD for about 20 days. I also tried the alert functions, etc., but they trigger without any specific reason regardless of the sensitivity, so I have disabled them on all cameras. I won't deduct another star because I didn't buy them for this reason, I already have an alarm system, I bought these cameras for this purpose (except for the limited FOV) and they perform well.