I’ve only been using them for a few weeks, but very good so far. The only drawback I’ve found is that they are only 10A. For the kettle and washing machine I’ve had to go elsewhere:
https://preflashed.co.uk/product/homekit-preflashed-uk-plug/
These are fused and can handle up to 16A. Edit: Not true - see later post. Also Tasmota and functionally exactly the same - but twice the price.
I have upgraded the firmware on all of them without problems - a single button click. Not familiar with Meross, but the entities sound the same:
The two makes are slightly different in shape, but quite compact and don’t foul the switches on your wall sockets (except possibly if you have USB sockets, when everything is a bit closer together).The Local Bytes plug is fractionally shallower.
As far as HA is concerned, you have to install the Mosquitto MQTT broker and then the Tasmota integration (all much more straightforward than it sounds). After that new plugs are automatically detected as soon as you add them to your wi-fi.
For monitoring I have found it better to use the power entity and convert it into kWh. You can feed the energy total value directly into the energy dashboard, but if the plug is ever powered off it resets to zero.
You do need to calibrate Tasmota devices for accuracy. Haven’t tried it yet, but it sounds doable. Instructions here:
https://tasmota.github.io/docs/Power-Monitoring-Calibration/
Worth getting one to check out.