The issue of pants test fabric

As I get my head and supplies together for my pants testing I have to make a decision about fabric. I know it is traditional to make a muslin out of, well, muslin but the fact is that I don't wear pants out of muslin like cotton fabric. When your aim is more to skim the body, or at least the lower part of this body, stiff fabric just doesn't work. The fabrics I like in pants are crepes, wools, linens and rayons, or a cotton, if it is a soft twill type. I also know from sewing that a pattern that works in one kind of fabric can be totally wrong, and fit quite differently, in another fabric. So I have decided to make my tests in a rayon blend. I will also need mega yardage, so cost is a factor and I fully anticipate producing multiple wadders in my quest.

Currently under consideration is this from Fabricmart a rayon pantweight herringbone crepe, and I am having good luck with Fabricmart this week. The colour is right. I am well aware, from having posted pictures of black garments, that it is impossible to really see the detail or to judge fit in them. The muslin colour is the right thing. 

Now I know in the back of my head that there are lots of good arguments for traditional muslins, like stable fabric when measurements are transferred back and forth, but I think myself that there is some value in testing in the category of the final product.

We will see.

Of course I have about 200 miles of black test type fabric in my stash and nearly as much red but I don't think that will do for testing purposes, although it will be nice to have that back up for emergencies.