} Nevertheless, it might be a useful "experiment" to add the MX RR.

It makes sence for all 'legit' email servers to have MX entries.  This would
reduce some 'small' load on the DNS system if outbound email servers didn't
have to do multiple DNS requests to find a host.  Granted a DNS request is
small and fast but if the first MX request fails you have to send another
request to lookup the A record doubling the work load for that request.  If
the estimate of over half of the email servers on the Internet don't have MX
entries that's a lot of extra traffic.  I guess I just like to try and save
space/time/money where its possible.  I hope my logic is correct here...

RM