My wife and I are travelling now, visiting our son in California.
We brought a Rimowa Sports Trunk (polycarbonate), 2 Topas carry-ons (alu), and a Notebook case (poly + cordura), all through the airport best known for baggage tenderness and handling sensitivity, LAX. Our experience over the decades is that if rough handling and damage happens anywhere, it will happen at LAX, arriving or departing.
Other than one minor scuff on the checked luggage this trip, no problems to report. The scuff wiped off the poly case using window cleaner. So no Jim Carrey-Pet Detective baggage handler types kicking our luggage onto the carousel encountered thus far on this trip.
Back OT: Be it an alu finish, a dipped gold finish, or sprayed matte black, the base of most Rimowa metal case products is alu. The reality is that what one sees online, or in a catalogue that would lead you to make a Rimowa Topas purchase of one model or another, is simply a new case advertisement photo, or rendering.
To some of us, it is a matter of function over form, meaning how light is the case, how well it rolls, and how well protected are the contents. Those would be the primary important features and considerations, versus the appearance.
That was my reasoning in making the choice. And I would never buy any product from a rendering, without handling and testing it first.
To others it may be the reverse, or form over function. The " Rimowa look." Or colour, or the rillen pattern stamped on the alu metal to stiffen it, or the fact that it is a well-made German product, with a Rimowa or LH stamp or logo on it.
Perhaps to some it is more expensive = a better product, or " additionally expensive = it is assumed to have additional features, a sign of sophistication and class, or that a celebrity that one might have a role-model association with, owns and has been photographed with such a product.
I have met one owner in Dübendorf , CH, who bought a Rimowa Topas case due to the fact that he is a jolly JU-52 aircraft enthusiast, which originally used the rillen pattern to stiffen the aircraft walls. Fine with me.
Whatever your reason, it is important and valid to you personally in making your choice. Just be advised that Rimowa metal cases will protect your packed contents, roll easily, can be serviced and repaired, but they will scratch over time. Depending on colour, some more than others.