Question for your DK Tank

Hey,
I was just wanting to ask a fellow dk tank a few questions and the ones on my server are a bit questionable. I remember Riggnaros from elitist jerks and when I saw the US first post on MMO (Congrats by the way) I figured whatever you're doing is working.
I noticed you still use stoneskin gargoyle even though I know a number of tanks have been experimenting with swordshattering (myself included) or even Fallen Crusader. Have you done tests with the other options that place stoneskin ahead?
Second, I saw that you're full mastery gems which is an idea I've been kicking around since I've been getting epics and my hp pool has been solid. As my guild is just starting 10m heroic modes this week I wanted to try out the extra mastery but I had one question. One of my professions is JC so I have the choice of specialty gems either 101 stamina or 67 mastery. Would you, if you were in my shoes, stick with the stam JC gem and switch the rest or would you even switch the 101 stam over to 67 mastery?
Thanks a lot for taking the time to answer and congrats again on 13/13.
Edit: Armory link if you have any questions gear/stat wise http://us.battle.net/wow/en/character/t ... r/advanced
I was just wanting to ask a fellow dk tank a few questions and the ones on my server are a bit questionable. I remember Riggnaros from elitist jerks and when I saw the US first post on MMO (Congrats by the way) I figured whatever you're doing is working.
I noticed you still use stoneskin gargoyle even though I know a number of tanks have been experimenting with swordshattering (myself included) or even Fallen Crusader. Have you done tests with the other options that place stoneskin ahead?
Second, I saw that you're full mastery gems which is an idea I've been kicking around since I've been getting epics and my hp pool has been solid. As my guild is just starting 10m heroic modes this week I wanted to try out the extra mastery but I had one question. One of my professions is JC so I have the choice of specialty gems either 101 stamina or 67 mastery. Would you, if you were in my shoes, stick with the stam JC gem and switch the rest or would you even switch the 101 stam over to 67 mastery?
Thanks a lot for taking the time to answer and congrats again on 13/13.
Edit: Armory link if you have any questions gear/stat wise http://us.battle.net/wow/en/character/t ... r/advanced