I’ve had just shy of 5 years of service from my Arca Swiss C1 Cube geared head, but the lower gearing had become notched in two places due to damage (a good hard knock on pavement will notch the gearing).
I sent it in to Robert Watkins at Precision Camera Works and it’s back. Repairs cost about $370 including return shipping, and wow is it buttery smooth and a joy to work with again! By far it’s my favorite tripod head for any deliberate work where I don’t need rapid ballhead movements. Want a different clamp than the stock one such as shown on my 'Cube? This can be done.
At about $1699, the Arca Swiss C1 Cube is not your everyday tripod head, but for the right indispensible for precision work and saving time with small adjustments, not to mention leveling. By the way, if you want the leather case I’ll sell you mine (unused) for half price.