Scott,
I'd just be sooooo inclined not to put it on these 2 types of coverstocks. Just got a High Energy - will leave it matte finish: somewhere between the stock 800 abd 2000 grit when it is drilled - will NOT apply Elixer to it.
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"...for advice is a dangerous gift, even from the wise to the wise...."
J. R. R. Tolkien