Like others have said the preheat oven time is longer than our 30 year old previous model.   This must be due to the fact the lower heating element is not inside the oven interior.   The trade off results is a larger interior cooking space compared to our 30 year old model.   We are getting used to the single knob to control time / temp / etc. an enhancement would be to add additional buttons / knobs to for some common adjustments.  Feels like this could become a high wear maintenance item...   Microwave works great and rotating glass platform is a nice addition from our previous model.    Microwave cooking time adjusts in 15 second intervals so while this is helpful in setting the time to 3 or 4 minutes our household would prefer an option to adjust in a finer time interval for some cooking items (popcorn...)