Just got my 100% in all of the TBoGT achievements
I did find this, which I wish I had found before I got about 70% of the missions to 100%:
A video of every mission to 100%, with some great tricks to getting the time on Departure Time, Dropping In, In the Crosshairs (which doesnt work for me, but climbing down the building did!!), oh, and Bang Bang.
The guy who made those videos is damn good at this game!