Hi!
Given this change in SURBL in policy and pricing, I would strongly suggest removing their rules from the SA rule base. Otherwise, you will likely get lots of complaints from users of systems that have embedded SA installs, or others who do not monitor this list. I can see many Barracuda users not having a clue why they are now being blocked and their systems are processing messages slower as a result.
By your reasoning, spamhaus should also be removed from default rules.
Many others have a high volume policy also. You end up with a minimal list. This is ok, but surprisingly operating infrastructure does cost time and money ;)
Bye, Raymond.