The SCRAM SHA-1 and 256 SASL mechanisms https://tools.ietf.org/html/rfc5802 offer better security than older SASL implementations. In particular the authentication information stored in the authentication database is not sufficient to impersonate the client if the database were to be stolen.
(The Java Broker already supports these mechanisms. The intention is to switch to recommend SCRAM instead of CRAM-MD5 shortly. One barrier to making this switch is the absence of support in the client).