I see. Thing is, even if I pony up for new hardware (Edge 840 etc), for all I know there is still no assurance that this issue will have been addressed.
True. I used to run into the issue on my 820 after ~ 4hrs. I did a ~2hr ride with the 840 running multi mode GPS, map, Nav, PM, HR, Cadence, Speed Sensor and Live Track. and used about 10% of the battery, so even if that particular issue is still there, it'd take ~18 hrs before it'd crop up.
I see that 840 has two models now, one having a solar feature. I wonder if that one is worth the extra USD 100 over its non solar counterpart. Thoughts?
Best thing is to check the DCRainmaker review for details on the dif between solar and non-solar.. That said, IMO, no, it's not worth it. Solar charge rate is extremely slow so adds little run time at the expense of somewhat reduced screen contrast.