At the time I bought this game it was cheaper than the current price which is 35 CAD. I got it for $29 which was almost worth it. The Single player is one of the best FPS campaigns ever made. It is right up there with the COD 4, DOOM 2016, and Half Life 2 which is saying a lot. As for the multiplayer I am not really into the COD style of MP which it has although the addition of Titans and a grappling hook are pretty cool I am just not into it.
I would say at the current price of 35 CAD it is worth it for the SP and MP but if you are looking just to play the SP I would wait for 20 bucks as it was so short I beat it in one sitting. That being said they have no season pass and all the added content is free which is awesome and might make buying it for the 35 on cdkeys. I might try it again when the horde mode is added but for now I am done the SP and the MP doesn't appeal (although I have note that people who like the COD style of MP say it is the best in its class).