Murambi: Only ever played the last MGS. It does remind me of the helicopter in 'Wasteleand', on MW2 though. Not sure if it is actually it.
Leon: This a screenshot with the 3 button on. I switch between 1 and 3 constantly, and work in both also.
This may be a little misleading as a wire though, as remembering the apache tutorial from this site, the guy's approach was, model now, clean up the mesh later, so you can see where, like around the cockpit area, and on the bulk of the body, there are tri's and 5+ sides, which I havnt accepted as final, but have gone with with the attitude of, 'I'll tidy up later'.
What I notice on your helicopter though is, say, around the windows, there is some definite panelling going on, like the pilots main side window, theres a protruding part that goes around it, following the outline of the window, and below that, the opening under the cockpit has a similar 'panelled' look, that looks (from your wireframe shot) that its actually modelled into the main body geometry. Its details like that stand out to me, that if I were to attempt similar, would probably end up causing problems elsewhere with the extra edgeloops they would create. Your topology looks so orderly for what looks like a very good, detailed model.