What is the Will of Deathbringers?

There is a decision that I will need to make soon. That decision point is when my last non-iLevel 264 item is replaced by Deathbringer's Will (DBW).

I am currently dual spec in Survival and Pet-tanking. I enjoy both. Survival is my raid spec. I provide replenishment and it is seemingly in short supply lately. But when this trinket lands I know that I can get a lot more dps by changing to Marksman. And not just Marksman using Agility and all my current gear -- but Marksman Armor Pen and all new gemmed gear. We're talking about getting rid of one of my two favorite talent trees and possibly all different gear in exchange for a large dps gain.

Here's the deal:

10707	Current gear and SV
10803	Current gear and SV and DBW
11349	Marks Agil with current gear (and T9.5x2)
11517	Marks Agil with current gear (and T9.5x2) and DBW
11559+	Marks ArP with essentially different gear and DBW

The "+" is because I haven't even looked at using different ArPen-focused gear.

So when DBW drops, I can just equip it and get ~+1% dps under ideal circumstances. Or, I can change talents, swap out gear, re-gem everything, and get over an 8% dps improvement. And as an intermediate step, I can try out Marks without changing much gear and get a 7% increase.

The problem here is that I only have dual specs, not tri specs. And of course it would be great to have a PvP-specific spec... I'm not sure how I want to handle it.