[mylife]

40 S&W makes more sense.

[MCF]

“40 S&W makes more sense.”
The 10mm auto might be better. drive a 200 gr. bullet at 1150 to 1200 fps. it would be faster than a 40 but operate at or below the pressure of a 40. It would have superior penetration compared to a 45. This is a big plus when shooting into a car.
Ether way they both offer a good compromise of caliber and magazine capacity.

[fireforeffect]

Neither .40 S&W or BREN 10 mm will be the chosen round. Both have a recoil impulse greater than the .45 ACP. Recoil was one of the main reasons for going to the 9 mm.