Im in a level 12 guild, with one team. its a new team, and im taking my time about it, as I already have an 85 or two, in the guild. My team is a bit of a mascot for the guild. They love to see me get on, and often, someone will ask me to drop my 85, and go get the team. Running old dungeons, and outlands dungeons, outland heroics, etc, I have single handedly gotten every "Guild Achievement" for dungeon since RFC. They love seeing the 5 toons ding, and seeing the 5 names announced as completing a dungeon, followed by "Guild Achievement!"