I didn't want to bump this but now that you did I can tell you that my wife heard great things about this cup because it truly functions as regular cup. So she happily bought it and low and behold it's strong point is most definitely its worst weak point.
The way it works as a regular cup is by not having a spout, you can drink it from all around the edge and the top piece is rubber that acts as the seal so if you just hold it upside down it doesn't leak or if it tips over etc.. but my kid (like every other) finds a certain delight by throwing it off the table and as soon as it hits the floor, splat! the seal gets moved from the force and out comes a whole bunch of juice, milk, water etc. This doesn't break the cup and it's still "leak proof" if you drop it inevitably the top seal will be moved and out come the contents.
So, buyer beware, you'll have to do lots of wiping/cleaning from this one.
