We use the JANET subscription to the MAPS RBL+. It is a frequent source of false positives which causes a great deal of irritation.
- Their RSS (relay spam stopper, i.e. list of open relays) does not have any re-testing nor any expiration of old entries, so is full of shockingly stale entries.
- Their DUL (dynamic user list, i.e. list of home computer IP addresses) has many errors. They do not track re-assignments of address space which caused them to list gmail's servers earlier this year.
- Spamhaus's ZEN list is just as effective but much more trouble-free. Why is JANET paying for the RBL+ and not ZEN?
- They do not accept corrections from their paying customers. WTF!
Sadly I can't easily ditch the RBL+ since using both it and ZEN adds 20-25% to our block rate compared to either alone, so performance would suffer horribly. Also, I don't want to get into the game of maintaining my own blacklist and/or whitelist - a time sink I do not need.