bokes

I once heard a good response here on BF about this question. It went like,"decide what is the largest folded size you could live with, and choose the best ride quality and 'ease of folding' in that size." I don't ride very crowded trains nor buses, so a 20" Bike Friday (451) works for me. I'd probably have an Airnimal (24") if they had a steel model that folded more conveniently (don't want to have to remove the front wheel for quick folds).

bhkyte

20" is fine if you don't need as compact a fold. Many ague there are not many advantages of going beyond 20" wheels. I tend to agree.Tyre choice makes a big difference to customise the ride to your needs.

JCFlack

I'm a Tokyo owner, and I'm quite happy with it - happier since I swapped the stock 6-speed freewheel gearset for a 7-speed set with an 11 tooth cog. The two problems you'd have with it is:
1. It is heavy - I wouldn't want to carry it up more than a flight of stairs. 29 pounds.
2. With the original gears it is slow. Even with the new high gear, it isn't fast, but it is fast enough for me now.

vmaniqui

i have ridden 20 and 16" folders. honestly i couldn't tell the difference between the two when you talk about speed. for stability they are about the same. but for folding convenience (which i need due to my multi modal commute), 16 is the winner, hands down. so what i am getting at to is - your choice should be dependent on the commute that you will be doing. if it's just for leisure biking get the 20 if you need it to go to work then 16 should be it.