Double-sided fold-out boot mat... for variable height floor only?

I like the idea of the double sided fold-out boot mat, which when folded looks like a two-section textile boot mat, but then can be reversed and folded out to cover one or both of the (folded down) rear seats, and even provides a bit of protection for the loading sill etc.

Trouble is, several sites claim that the part number I've found - 5E9061210A - is for vehicles with a variable boot floor.  I won't have that in my car and not sure I want it, from some of the posts I've read about it sagging when loaded etc...

For the Superb III, there are two part numbers for the fold-out boot mat - one for variable boot floors and one for cars without it.  Does anyone know if there's a version for the Octavia III that suits cars without VBFs please?