Both work very very well so it wont matter much. But if you really want to compare. The .270 starts with more muzzle energy, fires bullets at faster velocities (flatter trajectory+ less ETA to target) and the 150 grain bullets in .270 have better sectional densities than 180 grain bullets in .308
.270 also seems to be much more available during panic ammo buying, which may be something to consider. .308 is more popular, but this can be a bad thing now-a-days. If a lot of people have .308's it means a lot of people are going to need ammo for their .308's.
The .270 is a underrated cartridge capable of very long range shots, and proven it's capable of harvesting any type of game, with the right bullet.
A 130 grain in .270 should have no problem taking large hogs. A 150 grain could probably harvest 2 with one shot, if you line them up right.