I bought the cables. They are so reasonably priced I thought it was worth a try.
The Speakon connector is very easy to use; trying to fit my other cables' spades into those insulated posts with downward-pointing entrance slots is a pain. The back of the amp is really tight on space.
I don't feel the Benchmark cables were an improvement... it was more of a wash. Guess I thought something was not quite there, and in the end I put back my Omega Mikros, even though it's less convenient. But the fact that the difference was not hugely noticeable (in my system) points to the Benchmark cables as being a good value.