The oven thermostat is not going to hold and maintain a constant temperature of 350 degrees or any other set temperature. The oven temperature is going rise above the set temperature and it will fall below the set temperature in order to get an average temperature of 350 degrees.
I hope this helps! If you need a professional repair, call Sears Home Services at 1-800-4-MY-HOME.
The differences between the three I selected: 1) The most expensive has steam clean and air fry, with True Convection 2) The mid-range one has regular self clean with Convection (not True Convection), with larger 9.4" element 3) The lowest price has regular self clean, and does not have convection, with lower bake/broil element wattage
There are differences in dimensions as well. (I only see two stainless steel ranges with Induction and Convection.)