Parm I think this is a great use case for the Duo. I think a lot of people who are mad about the swappable burrs expect to be able to swap back and forth throughout the day, and, as easy as the burrs are to swap, that just isn’t realistic. It isn’t hard at all, but I certainly don’t look forward to the task. I tend to mostly do espressos, and maybe once a week I’ll decide it’s filter day, either because I am having company, or want to do a batch of cold brew, or I’m just feeling filter, so I do the swap, do all the filter coffees I want, then back to espresso burrs for another week. It’s a good excuse to clean out the grinder, and it saves me from having to devote precious counter space to a secondary filter grinder.
I could also see swapping the filter burrs for SSP lab sweets or MPs, and swapping between those and the Mazzer espresso burrs depending on the roast level of the bag of coffee I’m working on. Again, that’d be a once every few days swap.