I voted for the Rohr because of their cool propulsion noise and their cream colored interiors. I honestly like them all though, there is very little difference between them.
As for propulsion noise, I like the Rohrs the best. I have always liked the noise that comes from the 1800s in Boston, so I really like the Rohr's propulsion. I like the other propulsion noises that the Bredas, CAFs, and Alstoms make too.
I prefer the cream and orange interior a bit over the red white and blue one. I like the warm feel the older interiors have, however I do like the newer ones too.
I like that the Alstoms have interior ASA displays. Do any cars have automatic stop announcements.
Also, I do prefer the brighter orange LEDs than the older green ones.
All in all, I don't really care that much about the differences between the cars, because they look so similar, but if I had to pick a favorite, the Rohrs would be my favorite.
Bring double deckers to the north side!