Weak Clips
I clip the bottle to my purse during my food shopping trips and so far I've lost 2 bottles in 2 months because the keyring isn't very strong.  I haven't had much issues with the bottle leaking.  The caps are weak as others have said but it hasn't bothered me as much as the weak keyrings.  The bottles are durable but the keyrings are not.
Rating: 3 stars