I tried that spec last night on a new team with a ret pally, everything pretty much raped us unless there was a clothy in the group. But it was mostly DK's Pallys and Druids.
A double rogue team raped us the first 3 times, then we won against them 3 times. Kind of lame how a Nightelf could always see a Human first even though we both had the same stealth points in subtlety.
I went back to Mut-prep today, was much more fun with ret pally and seemed to work a lot better, at least for the 2 of us. I'm much more comfortable as mut then as Sstep.