Caps don't always go on correctly---easy to miss.  Otherwise, great.
Does the job, but the caps on the large bottles don't always go on correctly---they don't seem to line up right and have sipped off when I didn't triple-check to make sure it had latched.  This doesn't to be a problem with the smaller ones, so I guess it was something off-specification in the manufacturing of the larger ones.
Rating: 3 stars