Recent reviews by law-

You and three of your friends are gonna have a hell of a time. My group just finished the campaign on Veteran, without doing Normal first and it hit that sweet spot of difficulty. Just hard enough to challenge us without making us want to give up, but still requiring us to restart from checkpoints and re-think our strategy for the next few missions.
This game was much more fun than I expected going in and is probably the best money I've spent on a game in a loooong time.
I would say you should pick a group of friends and play all the way through to the end with them.

Good tactical gameplay

Great cerebral FPS. Reminds me of Bad Company 2 on small maps. If you play this game like COD you're doing it wrong. 1-2 bullets will drop an enemy so positioning and getting the drop on someone is where your mind needs to be. I hope this game takes off so we can see it alongside Counter-Strike in the professional sphere.