Not able to comment on that seat but wish a compatible one was available for my bike. I find that after just 10 miles, the seat on the new shape Grom, is uncomfortable like you are sitting on concrete. You are also locked into one position due to the pillion step.
As soon as a supplier releases a flatter, comfier seat, I will be first in the queue. I think that is going to be a must have for most buyers of the new Grom.