If there was a one line pitch needed to describe this film to sell it to a studio, it would be:
Independence Day meets Transformers
I don't think I can say it any better.
Good graphics. Some good side characters. No one I recognized, but that was fine. Solid acting given what was required. Decent writing. Everyone has solid motivation for what they do. Predictable plot line.
Worth a view? Yes.
Worth a buy? No. I'd rather watch Independence Day or Transformers instead.