Deciding on the "correct" cocktail shaker is a personal matter, and you are sure to become comfortable with any model you choose. If your concern is simply ease of use, a 3-piece shaker may be best. For experienced mixologists who might be looking for quickness, a 2-piece system of capping a smaller tin or mixing glass is often used, as is simply using a single tin for mixing and an ice strainer while pouring. 2-piece shakers are often sold as a set, and oftentimes appearance is important as anything. If you're looking for a little personality and ease of grip, you may want to try the Vinylworks shaker. Picking metal or plastic is something to consider when budgets and showmanship for both pros and beginners are important.