I always wanted to see how far the 1030 Plus battery would go in Battery Save Mode, after getting in excess of 50 hours during normal use.
Finally, I have that answer. I bought the Edge 1040, and as has been my practice, mounted the 1040 on the out front mount, while carrying the 1030 Plus in my pocket so that I could compare distance, elevation, riding time, etc. Finally, it occurred to me that I could put the 1030 Plus in Battery Save mode, since I wasn't ever looking at it during my rides.
Today, the charge was down to 5%, and I went back to late January and totaled my hours. The answer - 77.8 hours!
As far as the comparison between the two models, I've observed that the 1030 Plus generally shows more riding time and a longer ride distance, while the 1040 almost always shows more elevation gain.
The time for February was 14 minutes greater in 51h 37m, and distance seems to be about 2km for every 1000km.
For elevation, the 1040 usually measures around 20% higher than the 1030 Plus. (This could be a reason for some folks to upgrade!)