Just finished. From what I'd read, my expectations were high enough, but you blew them away with flying colours.
The attention to detail is amazing. The hulk background infos, the randomization of where the container is to be found. The blasted, sooty look of the container after the detonation! As if it went to hell and back - perhaps it did?
The music was very well chosen, and the visuals in general were simply beautiful. I can confirm that the checkpoint does indeed work on Linux.
On the downside, as Rodo mentioned, the missions are rather fast-paced sometimes. As a non-native English speaker I found myself going through the comm log quite regularly, especially to figure out the, uh, 'unconventional' controls. In other places, the mission is just on the edge of dragging on, mostly because of a wide mission space combined with the lackluster speed of the Mustang. It would be nice if diverting extra energy to engines would increase max speed, even if just a little.
I did notice one or two typos along the way (M1, "Fire your breaking
thrusters" comes to mind), and one little bug in the interface while changing my keyboard controls (there's a warning light with a bright green background). FSO compiled from trunk r9386, in case that's relevant.
Overall, a very high-quality release, and I'm looking forward to the full release!