Is Ghost of Tsushima a must buy?
To echo what MEguy11 said, it's a lot of fun. Kind of a crazy combo of Assassins Creed, Far Cry, + some RPG elements. Really enjoying the customization and skill trees areas and they're not overly complicated and labor-intensive, like some games. The story, while not TLOU-caliber or anything, is involving and there's tons of content across a huge map. You likely won't be bored.
The negatives? The camera can be a real problem at times. Get ready to stare at close-ups of walls at times while your opponent is pummeling you. There are some weird bugs in the environment that they clearly haven't worked out yet (my horse has levitated on more than one occasion) but as of right now, no game-breaking ones that I've seen. I'd definitely recommend it if you enjoy the games I mentioned above, and like digging into an involving story. It's also gorgeous to look at.