Collabora is correct.
Our standard accounts with 100% CPU Maximums, and premium accounts with up to 400% Maximums, but we don't expect the customers to hammer the server continually at these maximums.
If they did then the accounts would cost easily 10 times as much.
The limits are there to stop the "abuser" from hogging all the CPU, Memory, I/O or IOPs.
Like Collabora said if 1 of 500 sites was too busy the other 499 would be up and working perfectly.
We have to make the assumption that the 1 site using too much resource ("the abuser") is having a deluge of visitors, or having an issue with some recent code update.
If it is found that the customer is deliberately hammering the server, then that customer will be short lived on our service.
The OP would be better placed looking for a VPS, which he can hammer to his hearts content.
Also it would be interesting to hear what spec's they expect for their $5 a month.