I know money might be tight right now, but with a few more bucks you could get a johnson controls are a ranco which are both exceptional thermostats. i have never used any of those except the zoo med rheostat with the twisty knob, and i hated it. one of the knobs was out of calibration and would only go up to medium. if I had to pick one i would probably pick the first one. but i would consider saving up and buying the ranco or johnson controls if it can wait.