RBLs for SPAM Control

[Jeff McLaughlin <JMclaughlin () springsgov com>]

Does anyone have any experience with "pay for" RBLs in controlling SPAM? WE
use spamhaus but wondering if services like MAPS Real-Time Black List (RBL),
Relay Spam Stopper (RSS) and others are worth the additional costs.

Thanks any experience you can pass on.

-jeff