Except Goku killed Piccolo Daimao when he was a kid.  He is clearly much older now. 

It is more than not being green.  He looks nothing like the character.  Instead they have some bald pale guy in leather.  Piccolo Daimao still pretty much looked like any other Namekian.  It is the same for a lot of the characters.  Roshi is a guy in a Hawaiian shirt.  No bald head, no turtle shell, no sunglasses, etc.  Bulma just has a blue streak in her hair.  Goku is some scrawny guy with gelled hair.  Seems like they just chose random people for Yamcha and Chichi.

Look at all the comic book movies coming out and answer me this question, "Do they follow their respective comics perfectly?" They don't because following the comics exactly is either called a cartoon or an epic fail. Live action and comics are different mediums so directly translating one to the other perfectly is difficult and sometimes impossible. I'm keeping my mind open because I'd like to see more manga/anime live action movies done in Hollywood with decent budgets. Things like not having green skin are a bit superficial all things considered. We can disagree on this but I'm just a little disappointed no one is even taking a wait and see approach like myself when the movie is still months away from release.

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