I have one. I haven't used it extensively, and not at all for touring, but so far it's been fine. Currently it's on my folding bike, as a way to move my MTX bag between bikes more easily, because on my full-size bike I have a "normal" MTX rack. Haven't had a problem with it, but it's my back-up bike and, again, no touring. But the main reason I got it was for touring. I have an S&S coupled bike, and I'm worried that I won't be able to pack my normal rack for airtravel. I also have more of a bikepacking set-up with tent stuff in a handlebar roll and anything cages, and cooking gear and water in a frame bag, so the only thing my rack needs to carry is some clothes and food. I feel like the rack can handle that. But it's untried. Personally, for commuting, I love the Topeak system. I probably wouldn't use it for touring: I don't take the Topeak bag touring because it's heavy, not waterproof, and has unreliable zippers. And the rack itself it built for that bag and would otherwise probably be a little lighter and wouldn't have those ridges on the platform, which I worry will damage anything I put on the platform day after day. But I don't want a whole, 2nd set of racks just for touring.

I feel like a rack is easier to pack with my gear set-up, otherwise I'd probably be looking at a seatpost bag instead, and still may at some point.