Some of the best dogfighting you're bound to come in contact with.
In CS: HRTR, you complete various missions in different locales, such as cities, valleys, underground bases, and even Indiana Jones-esque booby trap-filled caves. In between missions, you go back to your zeppelin to upgrade your different aircrafts you have available. The campaign is about 6 hours, and features fairly good voice actors and cutscenes.
Multiplayer is also pretty fun. You fly around various landscapes from the campaign shooting each other, repairing your plane, and obtaining power-ups scattered around.
Considering this game normally should sell for less that $10 (if you can find it) it's definitely a worthy addition to the Xbox collection.