The Gravel King slick & M-Supreme are a very different tires vs the Big Ben, this is pretty obvious. While the GKs are a fast, light weight, foldable "gravel" tire, as far as I know, they are not available in 26 inch(559). I used the GKs and the Supremes as a comparison just to illustrate that I do have a direct, current, first-person, comparison to what are generally considered fast tires. I'm not suggesting the Bens are a match for either tire.
I run 26x2 Supremes (actually are closer to 1.7 wide) on my FL bike(spend months there in winter..like right now). I've ridden average/slow tires that feel like your riding in wet sand while actually riding on fresh asphalt..downhill. Average tires feel like you have to push them, all the time. Fast tires feel like there's no need to push them constantly to maintain speed..they just roll easily in response to pedaling. One might expect Big Bens to ride...average. They don't, they're fast-feeling tires(even better with touring weight) and are a pleasure to ride...all day.
How do the Supremes ride vs the GK Slicks?..very different, not at all a subtle difference. Both are fast, but the Supremes feel more...stout. Hard to describe. Supremes last a lot longer than the GKs too. I have two Lemond Poprads set up basically the same. One has a set of Supremes(37-622) on it, the other has a set of GK Slicks(38-622). This is about as close a basis for comparison as I know of.
Tire comparisons are hard. When talking fast tires, invariably someone will bring up GP5000s as fast..but they aren't available in 38mm+ nor are they available in 26 inch. They'd likely be too fragile for touring anyway. Supremes are nice tires, but they are gone. The Efficiency (Supreme replacement) are supposed to be better than the Supremes..but they don't come in 26 inch. GKs..nice tires, but they wear out too fast for touring(for me at least, I'm over 200 lbs and the soft composition wears faster)..and they don't come in 26 inch. At the end of the day..Bens come in 26 inch, they exist, and they ride nice, with or without touring weight. If someone has what they feel is a good/great/fast 26x2-ish tire, that's available, I'm all ears as I run four 26 inch wheel bikes and will continue to do so for the foreseeable future.
I'm still fretting the loss of 700x37 Voyager Hypers..that was a fast tire, but alas, it too is gone.