So I found this lineart image featuring the cast:



(whole version of it here) Anyway, I have a similar image from the Heroic Age design lineart library that I own, and I found this featured on a site that also talked about some of the other official merchandise from the series. Also the lineart itself is all legit. So Dio isn't actually as tall in the sequel that originally thought-- it's just everyone he's been around so far is a midget pretty much (Fam Gisey Millia Teddy). I'm gonna peg it at about 174cm, which is 5'7 - he was 165cm (5'4) in the first series. (until we actually get an OFFICIAL number but it'd only be off by 1 or 2cm hurr)

Seriously look at these caps he's like the jolly white giant in comparison.
http://i.imgur.com/w5HZu.jpg
http://i.imgur.com/1hCMh.jpg