I would like to try them as well. I tested the E21 shaft and found it to be extremely shock resistant and seemed to be very accurate although I only hit about 30 balls with the shaft. I was 4 under through 14 that day and finished even at 72 with 4 bogeys, though I was not playing with their clubs. I have been looking for a new set of irons as I have played with MIZUNO pro for about 8 years now and was thinking of the new Callaway X20 forged as they felt pretty good.
Let me know what you think as I might be interested in a new set.