[@ManoftheNorth]Hmmmm. I think Kasumi would work well with getting the Tablets, because you know it won't be all too easy, but at the time time she'd work well with stopping anyone from following with her mind tricks and distractions. 

Same goes for Master Grey, with his knowledge he could be useful but he has power, and that could help out with fighting off whoever follows them.

If I had to choose I'd put Master Grey in Group one, stopping anyone following considering he's more of a fighter than Kasumi. Then Kasumi to follow on to get the tablets as I've got a feeling her skills might be useful there.