The larger the # of nodes in a DAG the more resiliant it is as you can lose more mailbox servers before losing cluster quorum. You could increase the # of servers in the DAG itself, but have fewer DB ...
Right now we have a single Exchange 2010 server in a VM which has mb/cas/ht roles on it. We have VM level redundancy via vSphere HA (no FT) and the SAN but we don't have Exchange level redundancy. The ...