Tubus makes some of the strongest and stiffest racks made of steel. They are also very light and have the best warranty on the market. They are expensive however.

The Axiom weight rating is plain ridiculous, so personally I would be wary of it.'

The Topeak Super Tourist DX (the version with extra side rails) is a very good rack: reasonable well designed, strong, stiff and not that heavy. I have often commuted with more than 15 kg/30 pounds in a single pannier on that rack without problems. The extra rails makes it easy to use both panniers and strap something bulky on top of the rack at the same time. The rails also gives extra attachment points for bungee straps and prevents panniers to swing into the spokes. They also moves the center of gravity slightly downwards which is a good thing.

However, like most aluminum racks, it will suffer from abrasion from heavy panniers. I really don't think it will a problem for you for many, many years, so I won't hesitate to recommend it if Tubus racks are too expensive for you. It is perhaps better to buy a cheap, "good enough" rack and use some more on quality panniers, rather than buy an expensive rack and cheap panniers.

You don't need to buy rack and panniers from the same company. I like many Topeak products, but their panniers I have seen aren't anything special. Ortlieb panniers like the "Back-Roller Classic" are really excellent products; sturdy, waterproof, and so easy to take on and off because of their attachment system. Worth saving up for.

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Regards