All of mine are, where the light is as you would expect. 

I saw a video where an electrician (I think he was at least) was comparing TP-Link to other switches with a light, and used a temp gun. TP-Link had the lowest temp coming off the switches. I can't remember how hot it was, but wasn't much where I was alarmed. 

I've had some of the swithces in my house for 2 years now no issues.