I had my Edge 1030 Plus fully charged on January 1. I rode until I had 53 hours in, and the battery was at 13%.
I own the External Battery Pack, because a friend was planning to ride Paris - Brest - Paris, and we wanted to see if she could do it with the 1030 and battery pack.
So i connected the fully charged battery pack, and recharged the 1030 Plus to 100%. Then I ran the 1030 Plus down into the 85% range twice more, and used the battery pack to get back to a full charge. Finally, the battery pack was showing one flashing LED (5% charge remaining). Then, I ran the 1030 Plus to the end of February, and I still have 27% charge after a total of 128 hours riding time.
My bike setup is Garmin Speed Sensor, Garmin Vector power pedals (with cycling dynamics on), and a Garmin heart rate strap. I didn't do any navigation on these rides.
It certainly looks like Garmin's battery life claims can be substantiated!