GGB
Masterpiece
Regardless of whether I'm full of hot air or not, look up the amount of people online currently growing arakawa from seed (on this site alone) and selling them and you'll have to admit that at least the "bloodline" is chock full of imposters. I won't call out the grower I mentioned, because he's awesome, and my stance on the "cultivar status" not being real. but at the end of the day it doesn't matter anyway. If you want an easy to find coarser growing maple with good bark get arakawa, if you want one with a little more finess get one with nishiki in the name, described as delicate. Japan used a different system for it's varieties than the rest of the world for a long time, so even things like katsura have potential contiminants over the hundreds of years theoretically. I wasn't in Japan in 1910 so I can't say for sure that they do or dont.