I bought a few sheets on AliExpress, but I was hesitant to mount them on a blade (but it will soon happen from now on), because I had a great variety of sheet weights.
In the first batch I ordered, I got sheets weighing around 68 g, but I was picky because I had different sponge thicknesses (based on the sheets acquired later, the red sheet had an oddly thick sponge (~2.3mm), but initially I thought, that I got a too dense black sheet), so I ordered another set, but then more pieces of them each color.
Now I have a median of 72 g for each color, but I have a red sheet with 65.3 g and 78.8 g (!!), and also got a black weighing 75.8 g - at least, now every sheet has the same sponge thickness, except that one red at the very beginning.
I will report here back when I tried this rubber.
I have DHS H3NC and H3NP for comparison (I have Skyline TG2 (39) as well) - I also wanted to have a fair comparison with comparable Yinhe rubbers, but I have other issues with them. Yinhe rubbers seem to have less weight variance compared to Sanwei rubbers, but the sponge and topsheet parameters vary greatly compared to Sanwei, at least, Sanwei is a more stable contender here.
By variance, I mean, that I bought 2 pairs of Big Dipper (39), and the red side had a much more dense yellow sponge, than the blue sponge on the black side - but with nearly the same weight, the yellow sponge was significantly thinner (one of the red sheets has only 1.4mm thick sponge). Also, I have received a pair of Jupiter 3 Asia (39), which I mounted yesterday - the red sheet feels much less tacky than it is stated by reviewers, and I have a defective rubber topsheet on the back side, which is very shiny on the edges, but much more textured in the middle, and I could not even evaluate, which part feels more playable, so I ordered one more black sheet to see, how it should be.