We were on the Serenade in March and ended up in MTD. We dislike the large table setting and wanted a table for 2. When we went to try and change our table assigment we went to the MTD desk instead of the Matre'd desk. We were informed how it would work and absolutely loved it. We like to eat early so lines were not a problem. In fact we ate at 6 each night ( same as the first seating we originally had) we asked for, and received the same table each night ( table for 2 next to the window which I must say was magnificent as we spent one entire dinner sailing along the coast of St Lucia to the Pitons). We had the same waiter, head waiter and asst waiter each night who were among the best wait staff we have ever had.
We were in and out in about an hour which is what we like.
As someone else stated this is a personal choice. We like the dining room but don't really want to socialize with other guests ( not big small talkers), others may not like the formal dinner setting and opt for the Windjammer ( I believe Sonny mentioned this some time ago. Our wait staff knew our preferences as well as any other wait staff we have ever had and in fact this cruise was the first time I have ever added a tip above the recommended amount. That is how much the wait staff in MTD added to the overall enjoyment of the cruise.