A Great Shaker!
I haven't had this shaker bottle for long, but I love it.  I had another shaker from another company, and it would not seal tight at the top, and I would have to cover the top while shaking it.  Otherwise it would throw little droplets of whatever I was shaking up all over the place.  This one does not do that at all.  I seals tight every time, and does not leak at all even with a hard shaking motion.  I love the feel of this bottle, and the steel ball does a great job of thoroughly blending your shake (I use mine for mostly whey protein shakes).  I highly recommend this bottle.
Rating: 5 stars