I use them when I'm given a crossing that I could not normally make--IF I'm feeling charitable and don't want to make a point with the controller.
I also use them when I misjudge a descent--In my previous life, we were hammered if we didn't level off right at the required descent point. (Yes, I know you have 5 miles or so to play with but it was a point of pride for us or fuel savings or some such stuff...)
Anyway, I'm still in the habit of doing a 1 for 3 descent and adjusting on the way down. Sometimes you just need boards to help a little.
I'll understand if you bash me for flying a G550 like a DC9...
TC