I'm in the exact same boat, but I think I'm leaning a bit more towards GW due to it's particular focus on building professional skills. I get the feeling that SIS is trying to incorporate more applied skills into their program what with their practicum option for capstone course, but I personally feel that it's not quite as fleshed out as GW's. Still on the fence though. Hope that helps.
Does anyone have any experience with this gradual release of decisions? Should we expect it to go on over days? My browser might get worn out before then.