Is the two piece T13 worth it for PvP?

I wanna split this up into two questions.

How good is it for Random BG's, this is my primary source of fun and I wanna know if the extra focus is crazy for damage.

Also, how good is it for arena? (Primarily 2s) Also a good source of fun for me but I am usually the one getting trained (Usually roll with a Ret or Frost DK, High burst and armor plus the ret can heal). Is the extra focus worth the amount of damage you will be taking?
The hunter sticky on pvp on these forums suggests dropping 2 pieces of arena gear if your resil can take the hit and picking up 2 pieces of t13 for this reason only. picking up more focus helps us a lot.
It really comes down to asking whether or not your resil can take the hit.
it honestly feels like crap not having 2 piece on, doesnt feel natural. get 2 piece

once your like 4, 4.2k resil the 2 extra resil armor only provides 2-4% damage mitigation, which is like nothing
The resil loss compared to the damage gain is almost non-existent.

I couldn't imagine pvp'ing without the 2pc pve bonus.

Use the 2pc pve in almost every conceivable scenario, IMO.