I switched to +Strength and Sword Spec for 3.2.2. Most of the community seems evenly split on ArPen versus Strength right now, there was a poll in the warrior forums on Arena Junkies and I think the results were pretty close to 50/50. For me, I do not have PVE ArPen gear. I have a couple pieces, but we have a lot of plate DPS and don't see much of the gear drop. I also didn't have a Grim Toll or Mjolnir's Runestone (my dice are bad). The general consensus is, you definitely should go Strength if you don't have one of those two trinkets. And even if you do have one of them, some are considering going +Str anyway.
Personally, I think the sword spec buff is incredible, and +Strength lends itself a lot better to fast target swaps in 3s where your big damage isn't dependent on a trinket proc. I like the consistancy of +Strength, as well. ArPen was universally good during a trinket proc, and otherwise always good against prot pallies & DKs running around in frost presence. However, with the rise of caster comps in S7, I'd prefer the +strength for consistant pressure on casters.
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