I bought one of these for on the go. I liked the ease of being able to pop the top off and add your formula. I also appreciated that the top stayed on and didn't pop off or open up in my diaper bag. This little unit was so easy to clean too. I liked that it was so easy to turn the top to each of the compartments to pour out the formula. I like things that make a Mommy's job easy and this product qualifies. Items that take too much effort to clean are not worth it. The price for this product is just right and is a must have for any Mom on the go. The only reason I gave it a 9 was because I wish there was a better way to get all the formula out of the compartment without a lot of effort. The powder formula would pour out for the most part but there would always be some left behind because of the design. You would have to turn the unit upside down and shake and beat it over and over to get the last of the formula out. This may only have been annoying to me. Overall, it is a great product. I recommend buying one.