Yep, 300 Engineer here. The card *will* expire at some point, but I don't bother waiting. You can destroy the card and renew to get a new one. The reason? For every renewal you get a present from your trainer. I am goblin-my guy is in Gadgetzan. I usually do it 5 at a time(10 gold). I've been waiting and waiting for the recipe for the Pet Bombling, with no luck yet. I usually get stacks of bombs. I don't have a problem with the bombs, I certainly use them-but I want the Bombling! I believe for Gnomish it is a pet Lil Smoky. You can click on Trade Skills>by trade>engineering and look over the list for these Non-combat pets.