Amazingly Topps is worse. Main reason I quit buying UFC boxes.
Panini, while slow, give me decent info in their response (i.e. Just waiting on player X to sign, player Y has yet to return their cards).
Topps told me a red ink Overeem was on its way. Months passed, and while it still said pending they assured me it was mailed out, though they'd never reply with any requested tracking info. After a multitude of emails more months later, someone higher up ended up telling me that the card is still yet to be signed. Along with two other.
Only redemption I got out of Topps was a sticker auto.