The Ghost Brigades (2006)

Plot
A soldier in the Special Forces is given the memory of a traitor to humanity in hopes of stopping an alien invasion.
Better Living Through Technology
Human bodies are disposable, thanks to a process that allows consciousness to be transferred from one body to another.
Lowdown
A mix of Starship Troopers and Universal Soldier, Ghost evokes awakening, betrayal, and combat in the best military sci-fi tradition.