Last night I made a premade for CT where we all carefully wore as much holiday gear as possible while still meeting the ilvl requirement. Not only did we win a few of the dps "races" but I also picked up and held the giant without any problems during KB when the full +1 geared OT died to a meteor.

Moral of the story, just have an idea of what you're doing and you'll be fine queuing for whatever you want. Then sit on all the super geared dead people once the smoke clears.