I put somewhere around 600 hours into the first one. The main differences are the maps and weapons. Beyond that the gameplay is the same and the goals are the same for the online part of the game. The addition of Salmon Run makes it a much better game. I have really enjoyed playing this new iteration and hope they continue to supoort this game and make more in the future.
I don't like having to sit through that stupid intro every time I turn the game on. I also don't like that salmon run is only periodical. Otherwise, 8.5/10