I've had this oven for about a month now and I love it.  Easy to clean, no problems so far.  It does take a bit longer to preheat then my other "major brand" one did, but when it preheats to temp it is true temp.  The other one took a while to preheat but didn't reach true temp. So far, all I've had to do is just wipe it out after use. No residue or nasty built up.  Love my KitchenAid Dual Convection Toaster Ove.