My wife moves in between DM and GO each year depending on travel patterns. A few differences i have seen:

- DM call centre is much, much better. They answer instantly whereas the Gold line can take close to an hour at peak times.
- Gold rarely gets a greeting/water bottle onboard in Y.
- Not much difference in upgrades.
- no difference in flexibility if you need someone to push the boundaries of ticket terms. Both give a little but not a lot.
- priority boarding, J queue can often be enormous, F is rarely more than a handful of people.