Best protein shaker are those which meets your requirements. Professional bodybuilders require bigger bottle as compared to beginners. Requirements change from person to person. Someone prefer bottles that are economical but other don't mind to spend on expensive protein shaker.
Basically we select best protein shaker bottle on 6 criteria.

Volume of bottle
Plastic material quality
Blender ball for mixing protein powder
Easy to carry
Easy to clean
Price
These are 6 basic criteria to choose best blender shaker bottle. In addition to it, we prefer color choice, bottle design and brand. One should write down his requirements on basis of these 6 points and then choose which blender shaker bottle is best for him. We have selected 10 best blender shaker bottle from all brands on basis of these point. You can read details of all best blender shaker bottle here https://www.watershakerbottle.com/. Hopefully it will be helpful for you.