I have two sets- Dio Brando and The World, and Hol Horse and Joseph Joestar. I'm thinking of going for Jotaro and Star Platinum, as well.
Just to give you an example of the insane character design, here's a pic of Dio Brando, the mian villain, and his "stand" (psychic manifestation, basically), The World. Dio's the one who looks relatively human.
Just out of curiosity... can anyone take a guy with that outfit seriously?
(Joseph Joestar looks like an older Indiana Jones, whereas Hol Horse is a demented cowboy- their stands are handheld. Purple vines for Joseph, and a magical gun for Hol).