Invasion or Shattered? Its that simple.
Leave your poll result and why.
For me, Invasion.
Why: One: It has plentiful missions that are varied. Not just get out and shoot, you may have missions where you have to get a hold of something without shooting, all about speed. A mission where you journey inside a cube:

The ship models are also decent, granted, the textures are no-where enar as good as that on Shattered, the varied ship models to be used and various weapon systems make it excellent with playability.
Then there's something which I was sorely disappointed for SU not having: multiplayer. If you've played the multiplayer game, its really very nice, and very fun too.
There we go, what do you think?