Hi, I was wondering if anyone has experience with Ultratherm type heat pads on an on/off thermostat?

I have decided to use a thermostat that I bought that is on/off because it is industrial strength and should have much lower chance of failing. I have noticed that Ultratherm type heat pads I have, DO reach the desired temperatures, but it takes quite a while, like 30 mins before it is fully heat up. I want to use them because I tried them on full blast no thermostat and they were not hot enough to melt the tubs or anything. It would make the snake quite unconfortable but I don't think it would kill it in case any accident happens.

Now, the problem I see is, what if the thermostat is set to switch off and on at a certain temperature, and when the heat goes down, it turns the heat pad on, but it takes quite a while for the heat pad to FULLY heat up (although it starts heating up immediately a little bit). So, will that cause the temperature to fall MUCH LOWER, even though the thermostat has already turned the heat pad on?

For example, if the thermostat was set to turn on when temps from to 87F, and turn off at 89F. The temperature falls to 87F, and the thermostat turns the heat pad on. But it takes a while for the heat pad to get to full heat, so the temp falls to 86, 85, 84 etc... before it starts going back up? Or will the 'beginning heat" be enough to stop the temp from falling?

I have some flexwatt too, but haven't tested it yet. I hear it heats up faster but I don't know for sure.

Anyone with experience?