Mine will never see any mud or dirt short of a rally site! If I wanted an off road bike I'd buy something much smaller- I'm looking for a tourer with a comfy seat and suspension, plenty of steering lock, punchy motor and preferably a Guzzi. The Breva / Norge / 1200 Sport do nothing for me and I found the Griso too uncomfortable.
I think anyone buying a Stelvio for serious off roading will be either mad or seriously talented, 'cos it is a road bike, in my opinion!
Guy