The art style is awesome.
The poses are really well done. Even if they are similar, the subtle changes makes them portray completely different personalities. They fit the characters very well.
The only thing that confuses me is the clothes of Lapis. She appears to be cosplaying as something (I'm ignorant as to what she is dressed as and I really want to know) while Peridot isn't. thanks to that, to me, they don't look like they fit well with each other in this picture.