I only owned 1 folding bicycle so far, but I like the 5-speed internal hub gear on Dahon Vitesse D5. I chose this model rather than Speed or some others, because I wanted to avoid derailluer and its associated problems discussed above. It has good gear range for city and bike paths. No problem with bridges, pedestrian overpasses with ramps, etc. I could use higher gears to ride faster on flat road, but that's not very esseintial.