I have two Neff pyrolytic ovens, one is a double oven and the other is a microwave /oven combined.
The cleaning is simple, the turn of a switch and a quick wipe with a cloth afterwards, but they do use a lot of power to come up to the correct cleaning temperature. You can't leave in the shelves either and they have to be cleaned separately.
I tend to do my ovens at the weekend because our electricity tariff is lower for the weekend period