My Sept 2014 6800 Di2 is still perfect, after 8 years and 30,000+ miles. Yes, the buttons still click instantly, precisely. There's no wear in the derailleur pivots -- I can't wiggle the derailleur by grabbing with my fingers. The hoods are fine, the rim brakes are fine. I shift gears "all the time", often for just a few pedal revolutions, and a rough estimate is that I've done way more than 500,000 shifts. I can even shift with my ring finger while on the hoods--nice!


I swapped the seatpost battery at about 4 1/2 years old -- it still worked, but the time between charging was turning into "days" instead of "weeks".

It's quite surprising to me. I thought recently "maybe I should buy spares while they are still around, just in case" But it appears I can actually substitute a Di2 8050 derailleur in with my existing components -- good.