I think a spreadsheet would do a good job of answering this question.
I have been switching between Titanium Impact Band (w/+32AP gem) and Sealing Ring of Grobulus to see wich is better as a combat rogue, but I am still undecided. Prior to the patch SRoG was better, but with the buff to ArP I am not certain but I belive TIB maybe better depending on how it is gemed? I been holding out asking this and waiting on Vulijins spreadsheet but my guild is finally getting there act together, heading into Ulduar and I want to look my best. Any thoughts?