super dead Toni Hold antitopspin

 I need some help/information from some antispin specialists.  My coach uses anti on his backhand and has a stroke where he chops down into the table (often hitting the table) with his blade at about a 45deg angle.  He recently found an old blade with an ancient sheet of "Toni Hold - Antitopspin" rubber.  This stuff is really old, with a topsheet that is like ice and a super dead sponge underneath.  If you drop a ball from a height onto the rubber when it is glued on the blade, the ball barely bounces at all due to the dead sponge. 

Anyhow, his game has really gotten tough with this Toni Hold stuff, esp that chopping stroke close to the table.  The problem is, this stuff is so old that it is not ITTF approved any longer.  It appears that Toni Hold is still in business out of Austria, but they only make a "40mm" version of the antitopspin rubber.   My coach used this previously, and it was not very good.  The sponge was really poor and his anti junk balls weren't very difficult to hit.

I got him a sheet of Butterfly Super Anti Special, and the topsheet was nice and slick, however the sponge was much bouncier than that Toni Hold stuff.  He could not control the ball as well.  Does anyone know of any currently ITTF legal anti that compares to the super dead Toni Hold stuff?  Did anyone ever use this Toni Hold back in the day, and if so, what are you using now?

Thanks

Ive hit a few strokes with the ysaka anti power and the sponge is really dead.