I played with J1 on both sides on a Xiom Hayabusa ZL Pro (inner fiber blade, should not be as fast as AL Hexacarbon according to https://ttgearlab.com/2024/03/15/performance-indices-db-inner-fiber-blades/) for about 6 months, and if I'd go for the J1 again I'd personally try it on a MUCH stiffer blade (to combat the spin sensitivity in the lower gears). I think there's a very good reason the ZJK Original Carbon and New Era are rather stiff.
But I think the AL Hexacarbon would fare better than my Hayabusa due to the Koto outer layer.