Maybe it depends on where you live. Here (Bay Area) you cannot take an unfolded bike on the escalators, you must walk them up and down the stairs (lots of them). It is a big fat ticket if you don't comply. Having a bike you can fold with one hand quickly makes a huge difference. Rolling my Dahon Mu Uno to the escalator and folding with one hand while I step on (holding the railing) is smooth and fast. Even my Bike Friday pakiT folds down enough (not removing the stem) with one hand to use the escalator. If you have to remove a wheel, it's a two handed more time consuming job and you wouldn't want to do it very often I would think. Also, research shows that smaller wheels accelerate faster and I definitely notice even my 16" BF takes off faster than my 20" Dahon from a stop light. Maybe if you are a big strong guy the difference is minimal, but this little lady feels it, lol.