Broadly and generaly - 2 Strokes are more powerfull for a given engine size as compared to a simmilar 4 Stroke engine of the same size and weight but they are not more fuel efficient or as enviromentally friendly as the 4 stroke. That is what killed the 2 Stroke street production vehicles. My brother owned a Yamaha RZ 2-stroke street bike years ago and it had some work done on it. WOW! big power when it was "on the pipe".
These are not considerations for some military applications.
-Mark.