Bests & Worsts Reviews from Amazon

I bought these about 3 months ago for my 1-year old and have been loving them ever since. I'm back here reviewing because I came to order 2 more (who can go wrong with a straw cup that doesn't spill and keeps milk cold all day!?), when I saw all the reviews mentioning black mold. I immediately went to check all of my bottle tops and low and behold, found nothing. Not only did I remove all the little gaskets, but I actually broke an entire top just to be sure there was nothing in there. [for future reference, breaking the nipple is not necessary. You can simply pull up on the nipple or pull on the gasket from behind to see where the rubber meets the plastic] Mind you, we use these for milk on a regular basis. So for those of you who are desperate for a leak-proof straw cup and want to try this one but are afraid of the mold issue, here's what I've been doing for the past 3 months that have kept these things clean: 1) remove all attached gaskets and run water straight through the nozel before 2) putting the tops and bottoms into the top rack of the dishwasher for a 3) regular cycle with heat dry. When they come out of the dishwasher, 4) air dry on a Boon lawn or other comparable drying rack. 5) Store with nipple up/open, straw and gaskets detached. If you're *super* worried about it, you can put the tops into the Medela plastic steam baggies to sanitize once/week. I did this for a few weeks, but eventually stopped and it clearly hasn't been necessary. Good luck to future users! These are the absolute best straw cups on the market.