I'll first mention issues I had with previous shaker bottles that this doesn't have, first the ball is hard plastic and can easily go in the dishwasher, it's not a metal wire ball which is hard to clean or gets stretched out. The top doesn't leak while shaking. The cups don't retain much of an odor from previous shakes, and I've left a bottle for a week without it being cleaned.
A nice touch is the inside bottom of the cup is rounded, so typically everything gets cleaned out with a rinse under the sink, with a flat bottom there used to be crap left in the crevices that I would need to get in with a brush of some sort. For under $7 can't beat it.
This product is great ez to clean and mixes well in just a few shakes.