I'd say there really isn't much difference for CS Perks? I'd assume that in some different games, the tiers will give you other stuff, lets say Minecraft, they have different perks for different DS tiers, but all in all for CS you still get all the features of DS, doesn't matter what tier you get, as long as you get the 5$ one, you are good to go! (Regarding CS, for other games i have no idea!)
-
For a further guide, watch this video! if you haven't already.
CS has some perks only available to higher tiers that have been implemented recently. You can see a full list of CS specific perks here. (The DS Guide/Donate button in the navbar is outdated).