"I bought this set for my son, and after we put it together to play with, we discovered quite a few flaws with the design of both the Mech and the bike which make this set more frustrating than fun to play with.
The removable Samurai X blade just sits on the back with nothing to hold it in. It works if the model is just sitting there to be looked at, but it becomes quite impractical when playing with it as the blade will immediately detach. There is no way to lock the blade on to the back, which is frustrating when actually trying to play with it.
While the bike's front saw wheel does spin, it does not spin along with the back wheel but rather drags along the play surface. The entire bike must be tilted or lifted for the wheel to be spun. I was able to solve this by added a thin 1x4, a thin 1x4 axle, and small wheels to the underside of the front assembly. The small wheels stay fairly well hidden from site, the bike stays balanced, and at this height the blade will turn as the bike rolls along (adding another thin 1x4 will raise it completely from the play surface.) It's a total of 6 extra pieces, but they really could have been included to make this set so much nicer. Also, the place for Killow's feet to go on the bike is really poorly done, and while Killow can be put on the bike, it's not practical for play as he continually falls off.
Overall, I've been feeling like Lego has been cutting corners lately with some of their sets, and this one only reinforces that idea in my mind. These models don't feel as solid as I would like, which is disappointing for a $50 set. If you're looking for a set to just build and look at as part of a collection, this is fine. But if you are looking for something to play with, you might want to skip this one as it's going to be frustrating."