The flip-up straw makes one-handed sipping way easier when I'm driving or at my desk, and it seals tight enough that I can toss the bottle in my bag without worrying. Popping it down after each sip has become second nature.
Jacob Q.★★★★★
Took this on a hike last weekend and the leak resistant seal held up great in my bag, no drips on my gear at all. The straw flips up easy one-handed too, which is nice when you're moving.
Stella E.★★★★★
The flip straw snaps down with a really satisfying click and I haven't had a single leak in my bag yet. It's made sipping water at my desk way too easy, honestly.