I can assure you that the maintenance requirements are just as expensive on the Cirrus or diamond as on any Cessna or Piper, it is just the expense is in different places.
Take a good look at the items on both glass types with a Hard Life, the Cirrus for instance has a ten yearly ballistic chute repack and a life on the line cutters.
The other major problem is if you damage these aircraft as there are very few places that can repair any more than a minor surface scratch.