I'm on my 4th set of PR3s. My practice in the past was to try something new every other tire change then revert to what I liked the best. Before trying the PR3s I had resolved that PR2s gave me the best all weather traction as well as tread life, and ran several sets of them while trying most of the other brands. Once I tried the PR3s . . . I stopped experimenting with other brands and just stick with what I have confidence in and feel safe on, not to mention getting good mileage which when averaged with cost makes this tire the least expensive. Win, win, win.
As to cupping, feathering, etc. Since installing a TPMS system to monitor pressure instead of frequent manual checks which unavoidably let air out to be replaced - no cupping or other tire degradation. I discovered this with the PR2s and remains true with all the PR3s I've run.
I suspect the main cause of cupping and uneven tire wear regardless of brand is primarily an inflation issued. However, I'm no expert in any way . . . I just like to ride. PR3s work for me.
Shuey