The scale problem arose because I was doing something stupid - I spent a year drawing pure distilled water out of the steam wand (i.e. steam) and putting in very soft bottled water in the reservoir. It's only a question of time before the steam boiler becomes pure chalk...

In any event, I caught this one year in from brand new with zero consequences - the machine worked throughout. I am now regularly drawing water from the hot water wand and monitoring the hardness of what comes out to prevent a repeat.

I have had nothing but delight from my Duetto in the year I've had it, and I would heartily recommend it. Compared to similar class dual boiler machines I believe it has quite a few design decisions which are just better made and will result in greater longevity.