So I've been riding folders for a number of years now and I've basically come to the following bimodal conclusion:
1. Purchasing quality non-standard spokes, tires, tubes, wheels, etc is a pain in the arse. So for that reason it's really nice to stick with 700c, 26", or at least 20" wheels.
2. There's nothing inherently wrong with small wheels so if you're gonna go nonstandard then you might as well go as small as possible (ISO305 or smaller like 8" or polyurethane skate wheels).
How do you feel about it? I'm toying with the notion of replacing my downtube with a montague so I can buy tires and spokes at any LBS.