I built my bike and initially had the dual sided pioneer power meter. I noticed about a month after having it (wasn’t dropping watts in that time ) that it would zero out during sprints. Anytime I would sprint, power would get up to about 700 watts then zero out for a second or two then come back up to the 600s, completely missing the peak. In that time, I contacted pioneer and they had me troubleshoot some stuff over a couple weeks (they take a while to respond via email and their support hours are during my work hours) then would go out for a ride and wouldn’t fix it. And I hit my limit when I went out to do hill repeats on a short climb near my home where cadence drops to the 60s but not sprinting (usually 400 watts at most), and the power meter started zeroing out on that too!
I asked to return the item and they said I was outside of the return time frame, even after I brought up how I’ve been talking with them for weeks at that point and was inside the return period at the start of our emails. They said I would have to send the item to them to inspect for a couple weeks. Welp, I only have the one bike and the one crankset so that wasn’t going to happen during the season. They wouldn’t budge on it. About a month later, I ended up just buying a stages dual sided power meter. I reached out to pioneer to finally send in the unit to be repaired. They never got back to me.
In the end, I did a charge back on my Citi credit card in October, and I literally just got the refund taken care of a few days ago.
I will never deal with pioneer again. I had their single sided power meter prior and loved it, but I had no problems and never had to interact with their customer service. So if you don’t end up having a problem with your unit then you’re golden, but if you need customer service…best of luck to you.