Well, seeing as this is a Dragon Master set, I am a bit biased.
Piece wise its a very good set. Three weapons, a horse with a helmentthingy, the rare, patchwork dragon master. Not bad for 4 bucks. And I would quite happily buy it with the other part of the pack.
Design, meh. I'm partly for it and partly against it. I think its really cool that it is a chariot. A one of a kind thing. And the axes are a great touch. But, somehow, the whole thing looks a bit top heavy. It looks like it would easily fall over if it took turns to fast.
Playablity, hard to say. I imagine that, from a kids eye, it would be a fun set to play with. Perhaps nothing spetacular, but ok. For me, I would really enjoy having it slicing people as its charges down the battlefield.
I build, therefore I am.
Brave words coming from a guy called grapenuts.