We have earlier versions of these from the same company, and we're quite happy with them. If they get lost, it's not as costly as losing a Thermos, Kleen Kanteen, or something else. We haven't had issues with leaking, except for when the kiddos don't finish their drink and don't screw the cap on all the way.
While I'd like to get more, I'm a bit turned off by the boys / girls thing as well. Ours at least are gender neutral.