I quite enjoyed it, if you've played the others, you'll feel right at home with Primal because it plays exactly the same as the others, and there's the regular Far Cry style crazy characters and trippy bits. The pre-historic setting is quite novel, and although the weapons are clubs, spears, bows, etc, they are effective and fun to use, The spears were my favorite. The Beast Master thing was also quite a nice touch, where you can tame predators and send them off to attack enemies, or ride them to cover ground fast. The Bloodfang sabretooth tiger was the best beast to have in my opinion, was pretty much all I used once I had tamed him.
One thing is that it didn't feel nearly as big as the others, maybe because I had just come off Witcher 3, which was really massive, but it felt like it was a way smaller and shorter game than the previous Far Cry games.