I don't need a really big one, so I got this 16 oz one from Amazon. My protein shakes are just protein powder and almond milk. No complaints. I like that it has measurements on the side. Works fine, no leaks, easy to clean. I have it in green and orange because those are my favorite colors and match my kitchen. :-) That listing does have 22 and 24 oz versions if you need a bigger one.