I'm wearing this dress right now because it's the only long sleeved dress I have and so I thought I'd write a review.
First of all, it's very high quality. In the half a decade that I've had it, it hasn't ripped at all. The blue parts are a soft velvet; the red is a silky synthetic material. Unlike the doll dress, it doesn't have the glitter tulle overlay. The ribbons on the sleeves are just like the doll ribbons but bigger.
The sleeves are kind of itchy so you have to wear a shirt underneath. The skirt is very elegant, enough that I would go to a costume party in it--and I'm a teen.
Size large will fit a teen who isn't too plump.
The belt and crown are made of the same material as the doll ones. Some of the gems have come off over the years, but they have been used in a LOT of school skits--and the people wearing them didn't even know they were AG ;D .
The necklace is plastic, but it has stood up to a lot and not broken. It has also been used for myriad things in skits--including a turban decoration .