21.co's fee computer is much more accurate and in-depth if you want to estimate your fees.
I wouldn't say that. IMO 120 satoshis/byte is WAY more expensive than it should be. I have been doing transactions with 60 satoshis/byte and none of my transactions took more than 1 hours to get confirmed.
If they placed a low fee, you should try to accelerate it using viabtc's accelerator
He can't. 7 satoshis/byte is too low for their accelerator to accept the transaction. I believe that the minimum is something like 10 satoshis/byte.
OP's transaction already got 1 confirmation. I believe that it took 1 or 2 hours.
Pretty good for a 7 sat/byte transaction right?