Your daily driver is the obvious keeper. It's the one that fits your routine, that you trust to work when you need it. For me, that's something with a consistent draw and a flavor I don't get tired of.

Occasional devices can stay too, but question them. Do you actually use them when the mood strikes, or do they just sit there? If you only use a device once a month, it might not be worth keeping.

A quick way to tell: think about your last week. Which devices did you pick up? Those are your keepers. Everything else is just taking up space.