I rather like where the bombing scene finally ended up, I really wouldn't trade the opening between David and Weyland for anything. Wonderfully played, had a nice quiet tension to it, liked the added scope it feels like it gives the story, and a great use of characters from the previous film in an introduction. The crossing, at least as it stands in the viral video form, doesn't feel like it would've made as good an opening overall. Personally I feel the reveal midway through as a memory through David's eyes works really well.