I'm not voting until I have Leadfoot in hand, but at the moment, using the few pictures of Leadfoot I've seen as my only means of assessing him, it looks like Topspin is the best.
Topspin still seems the best from what I've seen of Leadfoot. My rating would be Topspin>Leadfoot>>>Roadbuster (yay for shellformers that have barely any movie accuracy!).