Am I on the right track?

[alittleFREE]

With the heat mat ur getting a thermostat is not needed. Just as an FYI it peaks out at 95. But my vote is for the 11x11 the other one seems to big. Compare it to a 20 gallon pad and it's huge.

Really?

That makes things a lot easier if that's the case.

And I might go down to the 11x11". Once I got out the measuring tape, 11x17" looked pretty huge..