They are actually all a pretty great set of Pokémon. I suppose Terrakion is good in competitive battling, since I've seen it on quite a few teams. Cobalion does seem to give off that leader of the trio vibe, as he does actually represent Athos, and as Kenshin5 said, he plays a cool role in Super Pokémon Rumble. Though, my vote is actually just going straight to Virizion, just because of meh shiny Virizion in White, but yeah, it does seem to have to most beautiful design. :)