Man, MOBIs aren't really my deal either, so I feel you there. And don't be ashamed about liking COD! There's a stigma against it, but if you enjoy it, let that flag fly, haha! Is A Machine For Pigs connected to the first Amnesia in many ways? Or is it more of a spiritual sequel, Like Bioshock Infinite?
It got a lot of flack for not being at all similar to it, so I'd say it's similar only in theme (amnesia..) and certain gameplay mechanics. Completely different story, gameplay, and even developer. It was good nonetheless though. It was developed by Chinese Room, who made the HL2 mod Dear Esther which is a must-play as far as I'm concerned.
You can definitely do it in one sitting. It's more a story than a game - it has immensely beautiful landscapes and scenes, and a great story and dialogue, but the interactivity is rather minimal, save from roaming around. I'd say it would pair great with a glass or two of red wine, or something greener if you swing that way.