IMO, if you can find it, loose leaf and using a bombija (metal straw with a sieve) are totally the way to go. I really find the flavor between loose leaf and the bags quite different. With that being said, the bag will give you a taste of what it is like and is much easier to find nowadays.
It's super easy to prepare, and this is another reason I prefer the loose-leaf. Just put some mate in a cup (say 1/4 - 1/3 cup of mate) and fill it up with hot water. Drink. Fill up, drink. Fill up, drink. When the flavor goes out, which depends on how much you put in, you can replace the mate. In the backcountry, when you're done, just throw out the tea (compostable), and there is no need to deal with the bag.
Like Chorpie said, it's hit of miss for some people, but I think it easily grows on people. It's easy to control how bitter you want it by having more mate in the cup, or letting the water sit longer
Flavor-wise, one of the most overlooked things is the kind of sweet aftertaste from it. Most people focus on the somewhat bitter flavor when you first sip it, but the taste is best at the end of the sip. It's a very grassy flavor but very hard to describe beyond that.
One of my favorite things about it, from a "caffeine" standpoint is the type of easy high-energy and high-functioning state of mind I get from it. I drink lots of different types of caffeine, several times a day, and mate is my favorite for getting me to work well.
Tenkara USA, founder
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