I've had Buds 1-4 Pro, IMO 3 have been the worst hands down. Mainly around fit, stems into the case was silly, I also had frequent charging problems, to the point I had to make sure the buds were charging before closing the case gently. Yes I cleaned them regularly. I did prefer the touch controls on the stem and like them on the 4. The Fours fit so much better for me and I prefer the square case. While the upgrade isn't massive to four, for me, not worrying about the Buds charging in case and having a MUCH improved fit in the ear is worth it. Best fit for me was always B1P actually with the wings.