Personally, I would have had an easier time accepting the stark differences in art styles had they been implemented in a different way. For example, it would have made the game much more interesting if each faction had its own style. Instead, each and every weapon on the battlefield (except, of course Aquila) looks exactly the same, regardless of faction, making the game feel like it's the 'Red Team' against the 'Blue Team', rather than an epic struggle between two different people. This also extends to each of the game's environments. This isn't to say the game's enviroments are bad looking, but I didn't see anything worth fighting for.
The sound is passable, but nothing to get excited over. The voice work is good, but not great, and the music is overused and fits with the game's generic sci-fi feel.