Brilliant! I feel like i say this far too often but i really did like the art style! The monochrome (monotone?) color pallete and thick blobby characters that didn't have outlines was just really very charming. I didn't like the smiling faces of the inanimate objects, they felt a little jarring especially since the human characters didn't even have faces! However the highlight for me was the animation. Great timing and sense of motion, fbf at it's finest! A bit of resizing here and there but mostly great. Especially the nicely choregraphed scenes with the two characters interacting.
The cinematography was neat too, the over the shoulder shot of the window and some well used pans and zooms really gave it a cinematic feel. However i didn't like the really zoomed out flying shots. They felt a bit cheesy and "supermanesque" and i much preferred the close up in your face shots of the characters.
The music was nice, shame it was longer than the animation and ended kind of abruptly! The concept was nice, the story was well paced and full of fun moments and the ending tied it all together neatly. I watched it 4 times before writing this review as i liked it so much, so it's a 10 from me!