They work fine, if you have nothing unusual setup for your domains.
It is highly recommended that autodiscover DNS records be setup for EACH domain, pointing back to the domain which actually handles the MX traffic for the domain.
In our case, securemail.chicagonettech.com handles all traffic, for all hosted domains.
So, every hosted domain has every one of those autodiscover records setup in their DNS and every one of them autodiscovers completely automatically from any device.
The difference between the call to the DNS records, vs the SmarterMail record, is that the DNS, on a domain-by-domain basis, gives complete control to the DNS, and not SmarterMail.
Phonr: (773) 491-9019
Phone: (224) 444-0169
E-Mail and DNS Security Specialist
Network Security Specialist
Customer Service Portal: https://portal.chicagonettech.com
Security Blog: http://networkbastion.blogspot.com/
Web and E-Mail Hosting, E-Mail Security and Consulting