Thermostat: Which is the best, and where to order?

[LeoMerlin]

Hey everyone, I've been looking at thermostats for reptile tanks to the point of getting headaches about it. I'm trying to find the right kind, one where the dial won't turn slightly like I've read, or won't take forever for it to start working, or not be exactly right as far as the temps go meaning it says one thing then a thermometer says the temp is either higher or lower than it should be. I've looked at the Zoo Med one, and Zilla and just not sure which one to get, or where to get them from. I want to have one so his tank won't get too hot in the summer time, or too cold in the winter. In the summer, my room gets super hot during the day unless it rains like today. In the winter, it gets super super cold. I may have to move him to another room in the house for the winter, where it should be warmer, but that's all I'll be able to do. Then again I may get a bigger UTH for him for the winter. I have a 10-20 gallon sized UTH that I had for his 10 gallon tank that I'm using on his 20 gallon long now. Any advice or links would be greatly appreciated!

NOTE: Right now his temps don't usually get too high, they did a bit when he was in the 10 gallon. I had spaghnum moss for his moist hide and that made the temps go WAY too hot so I took that out and used paper towels instead. Now he's in the 20 gallon long and the temps seem to stay where they should except at night which has me concerned.