I might be the only person around here that ordered a helmet. So no, I received neither the helmets nor the plaques, so hopefully both show up when they're supposed to ( a full year after the initially planned release).
Thankfully/unfortunately I never did get the Vader, so I never had any problems, but I also don't own it
I have the shock trooper on order with EE and picked up the 501st about a year ago on ebay. Fortunately the seller is also an authorized dealer and has kept in pretty regular touch over the item as well. Still makes me nervous though, waiting this long.