Late to the thread here, but I recently got a 54 Big Jack in KSF's muslin micarta. My wife helped me pick out the color, and since I got it I like it a lot more than I thought I would. It looks much better in person than in the pictures and I'm really happy with it. No complaints whatsoever! It's in my EDC rotation and I carry it in a belt sheath, but I do that for almost all my knives (including my little #14 Boy's Knife!) because I don't like much in my pockets. There were a bunch of Big Jacks in red river acrylic still available, but I just wasn't feeling the acrylic. There were even some of the cougar claw bones still out there, and now you're making me second guess the micarta. But I like it for EDC.
I got the Big Jack instead of the new #81 bull moose because I wasn't feeling the upended serpentine thing. The 81 reminds me too much of my Buck 301 stockman, whose skinny dogleg looking handle just bugs me. But I wanted a stockman with thick non-crinked blades and the 301 fit the bill. Anyway, back to the 54, I can see why they call it a Big Jack. It's very generous and confident in the hand, and I love both blade shapes. I can't decide how I want to divide up cutting tasks between them. I randomly open one or the other to do different things. Turns out being more fun that way!