I had to replace my 5 year old GE Profile double wall oven due to mother boards being fried. They no longer make that model so I had to purchase GE® 30" Smart Built-In Self-Clean Convection Double Wall Oven with Never Scrub Racks. Unfortunately, this oven isn't as nice as the Profile.
Replacement oven uses one on/off switch for both upper and lower, oven rack directly slide on sides of oven walls and are so tight it took the finish off the oven wall the first time I put the racks in, one timer for upper and lower oven, convection bake only heat to 350, Smart Built technology that allows you to use the Drop Recipe app (GE partners with this company and promotes them) doesn't work,  GE and Drop Recipe are aware there is a major problem which doesn't allow the expensive Smart Built to work.