Definitely an apple & orange comparison!

The Salsa shell does provide a little "give" so you can overstuff the case on the compression packing side since the zipper side will hold everything snugly - so in effect, you can gain an 'imaginary' inch or so of extra packing, but it is absolutely not the same thing as an expandable case.

The motivation for owning Rimowa is quite different than owning TravelPro or Tumi or other good brands. Since you already own a Salsa Deluxe, you should be able to judge for yourself if Rimowa is the way to go.

For me, I'm slowly converting all my checked luggage to Salsa, starting with the Sport Trunk and the 2 recycled 56" Cabin which have been replaced by the Limbo Cabin & the Topas Cabin as my carry-on. The durability & ease of maneuvering with the famous Rimowa multi wheels have become important considerations for me.