I think it's the most amazing FPS ever made. Nothing compares to the mechanics of just moving around and timing your spinfusor just right, and the tactics were more complex than just about anything. I honestly don't know much about Midair. I first saw screenshots which were not impressive, then when I saw video you can clearly see that the movement and scale of everything is clearly Tribes, so now I'm hyped for it as of a few days ago.
I think Tribes ruined me for most popular FPS since. While no other game came close to the movement of Tribes, the FPS games I've really liked since have been more on the strategic side like Natural Selection 2 and more recently Rainbow Six: Siege.