We are talking about $80 (or more) T-shirts here, so this is valid question. I think merino T-shirts are worth the investment. They offer considerable benefits over cotton and other natural fibers, as well as synthetics. Merino offers great temperature regulation, excellent moisture wicking, and they don't smell, which means you can wear them more and don't need as many of them. Three merino T-shirts in your wardrobe will last you as many days as 10 cotton shirts, so from a financial angle it's a wash. Here's a quick rundown of some of the benefits of merino wool: Odor-resistant : One of merino wool's superpowers is that it’s naturally resistant to odors. This means you can wear a merino T-shirt multiple times before needing to wash it. How many times? I'd say that depends where you are and what you're doing, but usually three to seven times. Our top pick is, after all, called the 72-hour shirt, because that's how long you can generally wear it before it needs a wash. See below for more on this debate.…