I have recently swapped my Suzuki Swift for a Honda Jazz - reason? The back seat of the Swift was too small for my labrador to get comfortable.
I know have the back seats of the Jazz folded down and a guard behind the front seats and a tailgate guard (both had to be custom made) and its just perfect, especially when we are at agility competions. Both dogs love it, Taz tends to lay down and chill out, whilst Kira prefers to look out of the window.