That was a factor in choosing the Carradice. I was very taken with the idea of being able to renew the waterproofness of their panniers. As nice as the Ortleibs and Arkels are, sooner or later (later I'm sure), they won't be waterproof anymore and nothing can be done about it.
That said, all 3 are high quality products. Honestly, if you flipped a coin and chose one by chance, I am sure you'd be happy with it. Look at the details and pick which set you like best.
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