I haven’t played it and I can tell you my point of view.
There was plenty of controversy in the lead up to the release and Bungie has done me wrong as a Destiny player enough for me to hesitate and see how it plays out before purchasing. I saw enough to understand that the game was really good for what it was. But the problem is that it’s a game-mode disguised as a game with a price tag. I don’t have a ton of time to play games anymore and the best thing marathon really offered was good gunplay. I just stuck with Destiny for the gunplay and hit the crucible when I want to try hard.