Hey guys, ever had any problems with 11 in wide flex-watt?

I heard that people have had their cages melt. Yes, I would use a thermostat...I just am concerned about a fire hazard and am considering using a smaller size ( with my thermostat of course ).....

I believe my Ultra-therm has hot spots so I am considering using flex-watt.

PLEASE give me your tips, experiences.....

Thank you,
Yosef