I've opened north of 750 bags (not including the Spirit Tamer bags) since starting down this road.
(that's actually a conservative estimate based on doing the tamer dailies every day since getting the Tamer achievement - it's not counting any of the bags I won before that, nor does it count the bags I earned leveling up)
I open my EK/Kal/Out/North/Cata bags all at once on my Mage.
Then I do the Pandaria dailies on my Priest and open all of those bags at once.
I have yet to see a single Porcupette
I have every Pandaren Spirit, multiple times over (enough to give my wife a full set, when she's never done a single daily).
I have multiple Flawless Whatever Stones (anyone want to trade for Flawless Undead Stones?).