My favourite part of this travel mug is definitely the mouth hole where you drink from, it’s so comfortable to use. And it is leakproof. My only downside is I’ve had other insulated travel mugs which keep my drink hotter, maybe I need to fill it with boiling water before putting my coffee into it? I drink my coffee quite quick so it’s not a major issue for me, but something to think about if you drink your hot drinks slowly. But overall I do like it and I love how sleek it looks.