We put a non-pyrolytic Miele in our last kitchen after our pyrolytic
Neff (sorry, Naff) blew up and was "beyond economic repair". Based on
the experience of using a regular oven, the new kitchen in our new house
has a pyrolytic Miele.
Pyrolytic ovens are very effective at burning off all the fat that gets
splattered on the roof of the oven. They also do a decent job at
cleaning the glass on the door, though do leave a rim of burned on gunk
around the seal where the heat doesn't get to as effectively. A quick
spray of your nasty chemicals sorts that.
What they do not help with is the racks and trays that I think are
usually the skankiest things in an oven, so you need to remember to
chuck them in the dishwasher regularly. Alternatively, you can place
them in one of those chemical bags you can buy in supermarkets.
So your datapoint from me is that I value the pyrolytic function enough
to choose one over a regular oven, but my Neff didn't last very long (8
years). Miele appliances are generally very reliable though, so here's
hoping this will last the 20 years I'd expect from Miele.
Jon