We have installed the mat during summer and will not know full enjoyment until this winter. From testing it in our air conditioned home the mat warmed to several different temp. settings, we could feel the warmth.
The installation went fine with the exception that a lead wire was cut during installation and went undetected until floor was installed. We were able to trace and repair the wire with exceptional help from Tech. Service. Not only was the product great so was the service.
Be sure to read and follow the instructions and there will be no problem.