heated floors sounds like the worst thing to happen to a metro train.

scenario 1: it's the hottest day of summer. the ac in the metro cars is obviously out and you're shoved into the car like a pack of sardines. but your feet feel like the first circle of hell because...heated floor.

scenario 2: all that food people leave on the metro just stanking and stay lukewarm on the hot floor allllll day.

charging units sound great though.