Based on a tip from a fellow enthusiast over at The Brotherhood of The Bat (A forum I am a founding father of, mind you!!) I have ordered a sample pack of Vytaflex 40 from smooth-on.com.
From what I read on the website, it is not only resilient, but takes pigment well. The aforementioned BOTB user also tells me that it's quite opaque once pigmented, which is really my prime concern. Some stuff I ordered from them before was rather translucent, and did not really meet my needs.