I played through them all a couple of years ago. They hold up great in my opinion, and 2 got a great remaster, so the graphics are solid. If you are talking about ODST specifically, then I’ll say it’s one of my favorites. It has a totally different feel to it that helps to flesh out the game universe a lot, and being so damn squishy makes the gameplay a lot different. There’s a sort of noir vibe to it too, so it definitely stands apart from the other games.