I suspect that I have a mild form of this, but have not been diagnosed. I am Type 1, so the symptoms from the low BG do not seem to be an issue for me ... I can usually match my insulin peak to my carb digestion with a simple bolus (not dual wave or square wave). My symptoms are primarily digestive in nature and I tend toward constipation rather than diarrhea. Most of the descriptions I find on the web list diarrhea as a symptom. Only a few list constipation, so I think this is less common.
My GI doc does confirm that my stomach empties quickly, but I have never asked him specifically about this diagnosis.
So far, I am having good luck with the FODMAP diet and Linzess. I have also had some success with Victoza because it slows down gastric emptying. Symlin was a disaster for me, it made my digestive symptoms worse.
I'm interested to hear if any one else has experience with this condition.