It all depends on your situation. There are advantages and disadvantages to both. So, I will give you my take on it and let you decide.
1. You are able to be done with the meal at an earlier time and feel more refreshed for the evening shows or swimming or just walking around.
2. You are getting a tad hungry again just in time for the midnight buffet!!
3. You can get in the bed earlier if you choose to.
Early Seating (Disadvantages)
1. You have to rush back from port for dinner.
2. If you are swimming or doing other onboard activitys, then you will need to stop sooner.
3. If you do get a bit hungry, you tend to stuff yourself way too much and don't sleep as well!!
4. Sometimes you may not be hungry that early.
Late Seating (Advantages)
1. No need to rush back to the ship while in port.
2. If you choose to eat somewhere different, then there is time to plan.
3. You usually are good and hungry at meal time.
4. No need to worry about the late snack munchies!! Your food is usually digested well by the time bedtime rolls around.
Late Seating (Disadvantages)
1. Too full for the midnight buffet.
2. You are watching the shows late at night and may start to nod off!
3. You may get a later turn in which throws off the next day.
There are probably more reasons both ways but I listed a few for you to consider. We have always had late seating but we have early this time because our daughter, who is 8, will be going. We think for us, the early time will work better on this cruise. We will see.
1992 MV Royal Majesty
1993 MV Royal Majesty
1996 Sun Princess
2007 Liberty of the Seas
2010 Navigator of the Seas
2010 Radiance of the Seas