And another thing.

Don't even think about a setback thermostat
.
Leave it on and leave it at set temperature. Even if you leave for
the weekend. Expect it to take 72 hours to stabilize after your 10
day ski trip when you do set it back 10 degrees.

Given the slow response time of radiant heat.... as per
your statement above..... is this one reason why YOu
might avoid using that "type" of heat?

Are ALL radiant heat systems just slow to respond....
and the nature of the beast?