To start off, I love this picture! Pinkie Pie looks so happy and punky! I really enjoy your drawing style. Something about the way their faces are drawn really makes me love this as true, original art.
Spike looks as though he's not putting his soul into it. Scootaloo was screaming like a metal singer, and I just don't get that vibe from Spike. His expression make it feel like he's just singing in a regular voice. Unless that is what you intended, then its fine.
I'm having troubles discerning where Big Mac's body is. I can see his head, but as for the rest, I don't know whats going on.
Other then that, this drawing is Amazing and really draws your attention, knowing it was well thought out and carefully drawn.
Let Pinkie Pie sing! LET PINKIE PIE SING!!!!! Spike: What? Why? I can sing well too, you know? Okay! Okay! After this song, then? Please? It's not that you don't sing well... she only seems to have one in mind that she can't wait to let it out... Spike: Uh... oh, alright. But are you ready for randomness because she can deliver big time... After seeing the way you three are dressed? Pretty much. Spike: You got a point...
urr.. no, i was just speechless at the time. all their expressions are great though, spike does creep me out a little, srry, just sayin overall, it's a very nice pic with vibrant colours.. think that sums up this piece nicely