I think you can state that hashlets are not as described and have been terminated without compensation and you can use the website marketing claims to support your case. I would not send the TOS as supporting documentation to your bank, because the TOS clearly states GAW can terminate the services at any time. It's possible GAW wouldn't even dispute your chargeback, but if they do they will likely use their TOS to justify their claim. At that point you may need to tell your bank that the TOS were not disclosed during the checkout process (which was true until recently AFAIK). Not sure how to deal with Paycoin and Hashstakers, it might be harder to explain.
That's just my opinion, you might want to ask around for more advice. I'm certainly not a credit card chargeback expert so take it with a grain of salt. Good luck.
Quoting for extreme usefulness
So, I just called my bank..and was told that since the product (hashlet prime) was received even though the 'value' was not as promised then that specifically I can not dispute.
However I can dispute the fact that I did not receive the product in the first place..