This unit replaced the wall oven my wife and I had used for 45 years.  With that, we had a bit of a learning curve but the process was fun, especially since it involved some discovery of its special features.  For instance, convection cooking is new to us.  We were pleased to find the oven has an air circulating fan within its perimeter jacket: that keeps the unit's heat from raising the interior temperature of surrounding cabinets during and after the cooking process.  The only glitch we've found involves that circulating fan in the jacket (note: this is not the convection fan), as it continues to operate a while after the oven shuts off.  At first when everything surrounding the fan is still warm, it's quiet.  In a relatively short time though, the fan operation starts to rattle, and that is disconcerting.  To this point, we have used this oven for 5 or 6 weeks.