For simplicity, I'm going to go with the Marik Xeno troopers, Comstar Marines, a Point of Space Elementals w/ Machine Guns, or a Squad of Tornado G13 PA(L) w/ Machine Guns.

Xeno Platoon: 0.5 Marine Points per trooper, 14 Marine Points total, 88 BV, 6.3 BV per Marine Point.

Marine Platoon: 2 Marine Points per trooper, 48 Marine Points total, 121 BV, 2.5 BV per Marine Point.

Tornado G13 Squad: 2 Marine Points per trooper, 12 Marine Points total, 119 BV, 9.9 BV per Marine Point.

Elemental (Space) Point: 5.5 Marine Points per trooper, 27.5 Marine Points total, 291 BV, 10.6 BV per Marine Point.

I'll take the Space Marines. Didn't do the math, but I bet it gets even more dramatic if you look at Marine Points per transport ton.