I agree. G-1 is selling like a hot cake in Japan so why change the formula.
G-1 is a unique ESN rubber. There is something about it that other ESN rubbers just cannot capture.
For one, its top sheet is very hard and very very durable. Rakza 7 and Rakza X match the durability of G-1's top sheet. Other ESN rubbers, sorry, are just not a durable as G-1 and Rakza 7/X.
Secondly the topsheet is grippy. Gripper than all the revolution series and Vega series rubbers I have tried.
Then G-1 is very direct. I cannot over-emphasize that. Where you want the ball to go, G-1 will get you there. I have tried a lot of other ESN rubbers, including C-1. G-1 is just really unique like that. So if you are a looper, you can loop very well using the grippy top sheet. If you are a hitter, i.e. Mima Ito, that directness and the power of the top sheet plus medium hard sponge is awesome.
2.0mm used to be the max sponge. 2.2mm? might be the max sponge now, only available in the past three or four years, so Nittaku is capitalizing on that.
Finally G-1 has some tensor catapult property to it but yet not as much as say C-1, Tenergy fx, Rakza and Revolution series.
Despite the grippy top sheet, somehow with its pimple structure and maybe the sponge, G-1 is also relatively spin insensitive. Meaning serve return is easier.
So G-1 is a very unique rubber and that's why it is the best selling rubber in Japan and TT11 I guess!
I am not using it now on my backhand because when I use carbon, G-1 on the backhand does not allow me to loop. Obviously that is a technique issue so I am using Rakza 7 soft and C-1 on my backhand to get my looping much much consistent. Will I go back to G-1 on my backhand? Not sure. I figured once I have my backhand sorted out, I might upgrade from Rakza 7 soft 2.0mm sponge to max sponge or eventually try Vega Pro/X to get more power. Do I need to go back to G-1? We will see.