Wow this is great information. I received some samples of Whip-it! 7x, 9x, and the premium. Unfortunately my numbers on the 7x and 9x read differently on the bottom. Does anyone have any idea as to why the 5x would be cleaner than the 7x&9x if they are coming from the same manufacture in korea? I have been offered some nice prices on some masters for all 4 grades of Whip-it! but can't decide if i should get the 5x for the cost or grab the premium for the quality. there is $150 price difference. Any input would be greatly appreciated.