Well, (human) twins usually are smaller...
I like the convoy look to it. The first movie had it when they were heading for Mission City, and Bay loves doing those sort of shots. With the right music behind it, it can be really inspirational having the Autobots rolling in to the rescue.
I hope they have some of these vehicles on display again at BotCon this year. Even if it is just the vehicle mode, it is like being in the presence of a live Transformer.