I have an old, out of warranty, 300mm f/2.8 L that has increasing, though still intermittent, problem with using the manual focus ring. It seems that the clutch mechanisum is increasingly failing to engage. a few weeks ago it would manual focus 90% or more of the time, now it's more like 5% of the time that it works.
Canon's national service center in my country will not give me estimate on the cost or even a ball park figure and given that, here, it means shipping the lens all the way across the country (I'm guessing at my own personal expense), then waiting (as not being a registered Canon Professional I don't preferential treatment) for as much as a month for a quote, then fixed or not fixed shipping it back (again probably at my expense).
Just wondering if anybody has experience with non warranty repairs to a USM clutch on their telephoto primes (or any other full time manual focus lenses) so I can, at least, guess-timate the cost.