I would guess that the life expectancy of Superspeeds to be similar to Artemis, if not a slight bit longer... In my experience, Artemis seem to be good for only about 15 years. Maybe slightly longer, if the table is in a controlled environment. My 9' Diamond is a Red Label, from 2009. It was converted to Blue label, in about 2011, using the same Artemis cushions. They have been banking sluggish for a couple of years now.
I've seen several Brunswick tables from the late '90's, with Superspeed cushions that are still just fine. However, I've seen many from the early '90's, which have dry-rotted, and required replacement. Supposedly, the rubber composition changed in the mid-'90's. I don't know that to be 100% accurate, but it would make sense.