Do I need a Terranium Liner?

[guidofatherof5]

That looks nice, much nicer than the one I currently have. I'm curious, does that one shut off the heat mat when it reaches the temp you have it set at and then turn it back on when it goes down to a certain point, or does it just control the power to keep it at that? My current one does the former, on top of that, the temp probe is huge, that one looks much sleeker and easier to move around and use.

It will shut off when the set temp. is reached then turn back on when it dropped 3 degrees below the set temp.