I was fortunate enough to play the other day in cooler weather. I play the Pro-v1x most of the time and that was the ball I compared the prototype ball with. I thought the prototype ball felt a little harder than the Pro-v1x. With the driver I found the prototype flew about 5 yards further. I also thought that was the case with the longer irons. When it came to the short irons it did not have the feel that the Pro-v1x had in my opinion. Not too far from it but just did not seem to respond as well around the green. Also the prototype seemed a little hard with the putter. Not much though. Overall I think I would stick with the current Pro-v1x vs this prototype.
PS. A friend of mine also played a few holes with this prototype and compared it to the B330 RX. He also thought the prototype was a harder ball. The both traveled about the same distance for him.