Here I go. I use the same stuff you do man and mine is 93 constantly on the hot side, 85 in the middle and 78 on the cool side. I check it 5 times a day using the rheostat. Sure you can spend 200 bucks on a real nice thermostat like a Helix or Ranco or Johnson and who's to say it's not a bad idea because yeah they are IDEAL but to say that a rheostat NEVER works... guess you've never tried because my temps have been PERFECT for the better part of 2.5 weeks and haven't wavered 1 degree... I have no idea why it got that hot. But I'm putting my 2 cents worth in because everyone is die hard into everyone going and buying a 150-200 dollar thermostat. Which is simply unrealistic for some people.