I have mine set so the temp measures 83-84 warm side. Right now, tho, three out of four of my corns are in QT out in the Living Room...in front of a huge glass sliding door. All three tubs have UTH's under one side and those are all plugged into a Ranco t-stat. The location sort of makes it hard to regulate their temps, especially the cool sides, but I make do.
The fourth corn is in the bedroom, where all of the snakes will be eventually, and in a 20L tank. His warm side is around 85, and that and the cool side (72-74) stay nicely stable.