I was hitting into an indoor monitor, so the actual ball flight is anyone's guess. But, the 61x felt a lot harsher than the 61s. I was surprised by that, because I really liked the x offerings in the B Asha line at the outing.
The Kusala are in my opinion on the strong side of the stated flex (or maybe true to flex) where so many other offerings play softer to flex. I have the Blue 61S and I struggle loading it enough at times where other stock offerings I buy in a stiff and it feels whippy, including the times I have tried the C Kua. The B Asha Stiff felt pretty good to me, but I'd still say it was a touch weaker that the Kusalas.