Recently went fury, need some gear advice

[Snitsky]

http://www.wowarmory.com/character-sheet.xml?r=Skullcrusher&n=Snitsky

So, I went fury tonight because we had an excess amount of tanks, and among the warriors I had the best fury set because I've been building one up. Anyway, I have two questions at this current time.

A) At what point do I want to stop stacking str/ap over crit. I read in the Fury warrior guide eventually you start switching from 8 str gems to 4 str 4 crit, and I was wondering if I should do that. As it stands now, my unbuffed AP In berseker stance is 1879 and my crit chance is 22.10.

B) Given my current trinkets, I'm going to switch Crusade out for Berserker's Call when it drops off of Zul'jin, but I was wondering if I'd be better off trying to get the Dragonspine Trophy.

I did the math for the Zul'jin trinket vs. Crusade, and assuming I pop the former every time the cooldown is up it averages to 10 dps per second ,whereas crusade only gives 8 when at 20 stacks, which it always is, but 10 is still more than 8. However, I'm not good enough with math or familiar enough with the proc rate of Dragonspine to know if it'd be worth it over the Berserker's Call.

Your input is appreciated.

[Invisniper]

"Fury is about Flurry. Flurry is about crit."

Suddenimpact and Jondoe are pretty much the only Fury Warriors, besides Wickedsick, on Lightbringer that I trust. From what I've heard while talking to him he keeps his unbuffed crit at a minimum of 33% and then stacks Strength. To me, stacking crit makes sense to trigger Flurry, but you certainly don't want to ignore AP. I usually roll with about 1680 AP, 151 Hit, and 28.06% Crit.

Edit: His Armory. (http://www.wowarmory.com/character-sheet.xml?r=Lightbringer&n=Suddenimpact)

Edit 2: Jondoe logged in his tank gear. Don't bother Armory'ing him.