The first sample I used Lamb's Pride Bulky Wool yarn for the weft. I chose that because it's the thickest wool I have in my studio leftover from some knitted felted projects and rug hooking. Although I don't know how it would wear as a rug (without testing it) it would make a great weight rug. I really enjoyed weaving this sample.
Next up another rug sample - I used fabric strips cut 3/4" wide. This would also make a great weight rug and I know rags would hold up well. From weaving this I can see having a fabric that is dyed all the way through would be the best choice - no worries about making sure the right side of the fabric showed. My white worked well, the gray worked well too as it was a batik and the same on both sides. The black fabric was a bit of a pain because it was a light grey on the back side and I had to try to keep the black side out, you can see in some places I wasn't successful.
I'm not a rug weaver but have woven them when I've needed a rug for myself. If I find myself needing another rug in the future I will definitely consider boundweave.