SMART water heaters detect your hot water usage routine and heat up water only when you will actually need. This way, avoid heat losses since water is only hot when it will be used.
So integrated SMART function is definitely worth it, but there are cheaper and more complete alternatives instead of buying a brand new SMART water heater.
If you feel comfortable with technology and programming devices by yourself, choose buying a programmable clock plug or a Wi-Fi one, programming it to turn ON only when you normally need hot water, simulating a SMART mode operation. You will need some trial and error to reach the right operation time, or instead just choose 3h before as default.
If you prefer to use the benefits of AI to self-program it for you, exploring all additional benefits like Wi-Fi connection, malfunctioning alerts and renewable friendly hot water, then KLUGITis the right choice for you.