All three of you seem to have had the MVP a long time and your finding it still works like new , I am curious to know what routine you all follow as far as charging , do you pretty much wait till it gets relatively low and then charge or do you charge it and keep it topped off much more often?
Many seem to think charging it often even if it doesn't need it is the best while others say let it drain more and then charge.
Surprisingly the ones who said they charge it constantly to keep it topped off are more often then not the ones that have had early failures.
Not unique to the mvp in particular,
but lithium batteries are supposed to last longer if kept charged:
Operating window: 3.3 and 4.2 volts;
the nominal voltage being in the middle: 3.7 volts.
I think if you reduce the window to like: 3.5 to 3.9 volts
it lengthens battery life.
It's like the battery is comfortable around 3.7 volts
the higher up from that you go, the more stress on the battery
the lower down from that you go, the more stress on the battery.
That's the theory anyway.