My 1 year old has a knack for finding the way to spill out the contents of her milk bottle so I was on the hunt for a straw type leakproof bottle and I finally found it. It’s totally leakproof, keeps drinks cold for 12 hours and so easy to clean in the dishwasher. I can speak to the durability of these bottles. We’ve been using them for over 6 months and they’ve been washed daily in the dishwasher and have held up so far. We originally bought one at a big box store and then ordered a second one here. They’ve both been used daily and look like they’re brand new.