In my opinion (i don't own a Brompton
), the Brompton (and now Merc) is a great piece of engineering. It is amazing how compact those bikes fold. The folded size is perfect for a lot usage. For me, since i don't fly often and don't take bus really more often (no buses in our 15000 peoples city), they would be perfect for car boot transport. I could nicely bring 2 in my tiny (by american standard) Chevy Tracker jeep. I could bring it in the office, at the cinema and all.
My biggest problem with Brompton and Merc is gear range. From what i read on Brompton Talk and this forum, a lot of peoples try to modify them to get a better gear range. Mountain/Speed drive, front derailler, 2 rear sprockets. I understand why Brompton do 3 speeds and 6 speeds bike only. I am not with them on this. If people want it why not build it?
What i prefer and could live easily with is 34", 41", 46", 52", 60", 65", 74". Sub-30" would be nice too. My Twenty do exactly what i want with this gear range. The folded package is far far from being as nice.
Note: I prefer derailler bikes. I was a bike mechanic for 10 years and i don't think i have seen more than 5 bikes with internal gear hub. Here, in Quebec, Canada i am sure no more than 5 bike mechanics can service a Sturmey Archer AW hub. From what i know, 3 speeds are efficient but 5-7 internal speeds hub are not that efficient. Maybe new 8 speeds are better.
Wouldn't it be nice to get as nice a folder as Brompton and a modern gear range on a
stock bike? Technically, do you think a 126mm 7 speeds rear hub with derailler would increase the folded size by much? If not, maybe Merc could differentiate them by building a version with a greater gear range ? Then, a front derailler would make this bike even better for some buyer. Maybe a market exist. For myself, a Merc (or Brompton) folding bike with a 7 speeds (30-75") gear range (more with a front derailler) would be a perfect commuting/touring/travelling bike.
It is a dream. Bike are marvelous simple machine. The best machine ever in fact!