Bike Friday has some conflicts because their 20" wheel bikes are what they made for a lot longer.
for touring, so touring , is likely to have them suggesting one of the knock down bikes , with 406 wheels.

one advantage 406 tires are second behind 559 MTB tires in world wide availability.

Though people have taken their Bromptons, the 349 wheel common with the Tikit,
Around the world in some pretty remote places, where the fold to get on a rural Bus with the locals
or hire a dinghy to get you across a river is much easier to cope with , on a folding bike than a big wheel MTB.