I bought the HS110 5 years ago and for some reason they have skyrocked in price. I assume they are discontinued. I also have a Samsung plug that does the same thing but not as elegantly but that's off the market too. I thought the days of energy monitoring where over but no! Here it is where the HS110 shoppers may not be looking.
My goal has been to eliminate everything in smart home that isn't SmartThings after switching ISPs and needing to change the WiFi on so many devices. It was like pulling teeth. Kasa the exception. Their app is better than SmartThings and very easy to setup. It is better at handling a dual SSID network where cheaper products require that you turn of 5Ghz so it can find 2Ghz. But those cheaper products don't offer energy monitoring and that's why we are here.
Not only is this a cool feature in general, it can help find surprising energy draws. Right now my office setup is running 283 watts total. That goes up to 290 with a 3 way LED bulb which is too be expected. But if I go up to the highest setting it shoots to 313 watts. This means 7 watts more for the light but TWENTY watts more if I turn it up.
I have four monitors. They go to sleep with inactivity such as the computer being turned off. BUT, I found out that they were still using 30 watts in this stage.
The timer feature is great. I set it to turn the monitors and light off at midnight to encourage me to go to bed. You do not have to program an "on" to have an "off". I use voice commands to turn off the monitors if I'm going to be away from my desk. Setup a group in Alexa and I can control turning on the lights, monitor and computer if they are off.
I also recommend an HS300 which is almost too good to be true. SmartThings, at least on my phone discovers and allows me to control Kasa devices is so everyone is playing nicely with each other.
It will take time to recoup the cost of the smart outlet if you are buying it just for energy monitoring but it's the convenience of the app and voice control that is primary. Through careful monitoring, I can knock a 1/12 out of my electric bill. That may not sound like much but it's one month free electricity for me.
Finally, move the plug around to test different appliances, etc. It has encouraged me to shut down my computers at night which are all hooked up to monitors. The daily average as reported by the app can be multiplied by the cost per kWh which in my case means my workstation is costing me 40 cents per day.