I love the entire experience of the MDR, I loving going right to "my" table - no reservations, no waiting. Being served by a waitstaff that knows my preferences. Not having find a table and then juggle plates and wait at food stations. Having time to sit and relax and talk to DH and tablemates. Not being rushed by people standing near your table waiting for you to vacate it. Did I mentioned being served??
That said, those times MDR is not an option (Lunch on port days) we have done the buffet and don't really enjoy it -The food is just not very good and, well, it's a buffet. We usually just eat a largish breakfast and get a Guy's burger, pizza, or buritto or deli sandwich ( They are all very good - much better than buffet IMO) for lunch to tide us over for dinner in MDR.