I have a 5.7 and a PS90, and they are my favorites. Ammo is less than a .45. You can't safely reload that cartridge from what I hear. It is a very high pressure round. Accuracy is stellar, and don't believe he haters, it is a potent round. My old man took out a coyote in the back yard, and it ripped a hole the size of an orange out the ribcage coming out. It is my go to woods gun. If I get rolled by a grizzly in KY, then my luck just ran out... It weighs less loaded with 20 rounds than a Glock 19 unloaded. Lots of muzzle flash, and no kick. Great gun for the ladies as well.
The PS90 is just a blast but expensive to feed because it eats quickly!