Never heard of GreenManGaming, but for what I can see is kind of an external Steam?
I am still uncertain to buy the game or not. Not because of its quality, which is very pleasant (I have seen quite a few Let's Play Cities:Skyline), but I have a very small amount of free time, which means if I buy it, I might need to dump all my free time on it.
Any thoughts from someone who is playing on how much time is taking them palying the game and so?