I also received a full set of acrylic plates instead of aluminium top plates. I actually ended up using the top-most acrylic plates to improve the look of my ErgoDox, by leaving the protective paper on the under side of the topmost plate:
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It looks pretty good. Bamboo-like, even. Perhaps not as nice as metal, but warmer to the touch, and an acceptable work-around until the aluminium top plates arrive. (-: