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Overall, I wouldn't hesitate to use and recommend the Surley rack and treat the failures as special circumstances and likely rare. I am more cautious with the hub failures. Probably OK for others, but for me I have intentionally tried other hubs instead for a better in the field maintenance and sense of reliability when I am more remote.
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I bought a Surly front and rear rack. Initially used both for touring, but after two tours decided that the front rack was overkill for my uses. Donated the front rack to a bike charity. Bought a Tubus Ergo to replace it. On a different bike I use a Tubus Tara on front.
Rear Surly, I still have it and use it on my heavy touring bike for riding around near home, the wide platform is nice for that. But for touring, I use a Tubus Logo EVO on my heavy or medium touring bikes. My light touring bike gets a Racktime Addit rack in the rear. I think both the Tubus and Racktime are stiffer than the Surly, even though the Surly clearly has more metal in it.
Thanks for the additional info on your hub issues. My rear hubs for touring are the older design steel axle Shimano XT, 36 spoke. Very happy with them and the quarter inch ball bearings makes me feel confident with them. Also have a Rohloff on my heavy touring bike, but that is a total different topic.