I've been using the CUPKIN Toddler Tumblers for a few weeks now, and they're definitely a mixed bag. The powder-coated stainless steel looks sleek (love the brown and peach combo!), and the stackable design saves space in my kitchen. My toddler loves holding them—the textured grip prevents slips, which is a huge win.

However, the 'leak-proof' claim isn’t entirely accurate. While the silicone seal around the straw does reduce spills, it’s not foolproof. My kid once shook it vigorously, and—yep—water escaped through the straw hole. Also, sucking through the straw requires serious effort! My little one gets frustrated after a few sips unless I slightly loosen the lid (which defeats the leak-resistant feature).

Durability is hit-or-miss. One cup survived a drop onto tile with just a tiny dent, but another started leaking after a similar fall. And while I appreciate the dishwasher-safe lids, hand-washing the cups (as recommended) is tedious when you’re already drowning in toddler messes.

Final thoughts? They’re stylish and functional for *gentle* use, but if your kid is a thrower or a vigorous drinker, these might not be worth the premium price.