I've had good and bad experience with DMM. All the important stuff was already mentioned above, though. Keep in mind your mileage may vary quite randomly. That would be depending on the time of year, time of day, position of the moon, and (as somebody already mentioned) how the immigration officers are feeling at that very moment

One thing to note is, that the LCD screens at the baggage carousels don't always show the correct info. It happened to me twice that my EK flight was shown on one, but our bags were delivered onto a different one.
Ask one of the trolley service guys (in yellow shirts) to check if your flight will actually be on the carousel it is supposed to. They seem to know somehow...