I don't know if that's really anti-slip, or just the rough texture of the big steel.(?)
Anyways, I love this build, bro. Everything looks dead-on to me. I've always had a thing for the Abrams, and yes they're still carrying ALICE packs/rucks all over the sandbox. Makes us old-timers feel like it's still the same Army, as long as they've still got some of the old equipment.
I was considering a build of a USMC A1Heavy called "Stink Fist", but I backed off when I saw the kit price. I still might do it later this year, though...