No, they did not - as far as I know. Most of the reactive and proactive/particle coverstocks were derived from PK 18 - which is still in use on the Nemensis and the Time Zone. Maybe the Warp Zone shell is close to the Detonator coverstock, but the original beefed-up PK 18 materials "died" with the Fuze series. The Activator coverstock has taken their place.
Maybe the PK 20+ coverstocks in use with international balls are related to the Fuze coverstock, but that is just a guess.
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DizzyFugu --- Reporting from Germany
"All that we see or seem, is but a dream within a dream..." - Edgar Allen Poe