I have Energenie MiHome sockets, lights, and eTRV's fitted. The units are ITTT so in theory no limit to what you can do, however the light and socket units have just three events each built in. In my case for the sockets the idea was they would power the alarms used to protect my mum, we wanted the alarm to switch off at the times her carers are due to visit, I could have really done with four events, as it is from 12 midday to 6 pm the alarms as default are off.
The idea of the socket was we could not forget to turn it back on again, and if I went out leaving my wife in bed, I could reset the alarm after leaving the house. It has four ways to turn it on and off.
1) Button on socket.
2) Remote control we actually have two.
3) Smart phone or PC.
4) Timers.
Plus any ITTT app for example if the weather report says it's going to get cold.
As to fitting you need a deep box, there is not much spare room, with the light switch you need to remove any top or bottom lugs or bend them back, the light switch does not require a neutral and the LED on the switch is lit when on, the switch is used to power a 10W LED bulb, which is dimmable came from B&M bargains so nothing fancy. As with sockets you can have three set on times. I used light switch because I am lazy and did not want to pull in cables for a two way switch. Since I had to change the back box for a deeper one, not sure it was any easier.
All the units connect to a hub which in turn connects to the router. The eTRV MUST have the hub, without it no way to program, the lights and sockets don't need the hub to work with remote or on socket button, both cases red LED shows on. To work with phone you need hub, but will work direct or with remote without the hub.
The built in wall sockets do not monitor the power used, the plug in adaptors come as three types, same as wall socket you can only switch on/off no monitoring, with monitoring only you can't remote switch on/off, and both monitoring and on/off. Why the wall sockets do not have a monitoring version I don't know.
P.S. they were easy to set up, the eTRV's did give me some problems, I think down to house rather than the units, but no problems with sockets and light switches.