Main advantage of the short mags is the size of rifle they come in. There aren't any great advanges in the actual performance of the cartridges, only their size. Its allows gun makers to make magnum rifles that are very compact. I looked long and hard at getting a 270, 7mm, or 300 WSM when I was buying a new rifle last season, but I ended up buying a regular 7mm Rem Mag instead because the ammo was quite a bit cheaper and I wasn't looking for a compact rifle. If I wanted to get a good, lightweight rifle for backpacking in after elk or backpacking back into the wilderness after sheep, but still wanted magnum power, I'd buy a short mag.