If they're melting, your snake will be fried! The ReptiTemp will keep things just right, though. I got mine from Amazon too.
Do you have an AcuRite to guage temp and humidity? The probe goes right on the warm spot, so you'll know exactly what temp it is. I use about 4 sheets of newspaper, plus just enough ReptiBark to cover it. Took me 2 weeks to realize that the inch of ReptiBark gave too much fluctuation in temp on top of it all.
We didn't care much for those tiny nubbles that come with the ZooMed UTH, so dh raised the tank up by an inch or so just with short strips of wood, kinda like the 2x4 type.