From my experience cc1 and cc3 are 1 key each, and cc2 is 0.5 of a key. I've traded quite a lot so I think I wouldn't be wrong calming it's an average rate
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Also I think the reason why crates are worth so much is simply because RL crates pay off. It's not like CS:GO cases where u got 0.01 chance that your case will pay off, in RL the worst you get from crate is rare item, which is ~1 key on its own, and besides that you got quite a good chance on getting import and exotic items. So far I've opened ~20 crates and items that i got combined are worth ~50 keys, so either im super lucky or RL cases are simply worth opening.
Last edited by Smaguris; Oct 20, 2016 at 03:35 PM.
Reason: <24 hour edit/bump