Weapon / spec questionFollow

Apologies in advance - I DID look at the spreadsheet, but can't get an answer on a gearing question from it, so I figured I'd turn to the rogue forums.

So since dinging 80 (forever and a day ago) I've been running Mutilate on my alt Rogue because that's all I've had the weapons to support. And for an alt, he does pretty solid DPS at this point (~4600 on 10man Ignis as a recent benchmark). I've really wanted to try out a combat offspec though, especially since some of the revamps upped its DPS.

Last night, I got into an Ulduar 10 run and got two possible pieces for Combat - specifically Razorscale Talon and Kinetic Ripper.

Obviously the ideal solution if I want to try combat would be to get a nice OH like this, but until that time I'm looking for the next best solution.

I could OH the Kinetic Ripper with 5/5 Hack and Slash or I could pretty easily pick up a Grasscutter until something better drops.

Sadly, the 3.2 combat SS at EJ doesn't go back far enough for me to get an answer -- can't get it to display Grasscutter or a few of my other pieces (H-ToC5 drops, old Naxx10 drops) that haven't been upgraded yet. I'm almost completely sure the +DPS from sword spec procs will outdo added DPS from Combat Potency procs and the higher OH DPS #, but I'd like some confirmation before I go wasting badges.

So the question: With 5/5 Hack and Slash and MH Razorscale Talon (163 DPS 2.6 speed sword), would Kinetic Ripper (163 DPS 1.5 speed fist) or Grasscutter (143 DPS 1.6 speed sword) OH give better DPS?