The 50 Beowulf is a great big bore caliber.I debated a long time about it before I put my 458 SOCOM together.
There are several guy's here that have the 458 SOCOM. I chose the 458 SOCOM over the 50 Beowulf,and the 450 Bushmaster because it uses a .458 caliber rifle bullets,where the others use bullets designed for pistols,and there isn't near the selection of bullets to choose from with the pistol calibers.
If you plan on doing any amount of shooting with these big bore calibers,you better know or learn how to load your own ammo.The cost of factory ammo is very expensive,and even reloading these calibers isn't cheap.
Depending on the bullets I choose to load,it still cost between $1.35-2.00 a shell,using virgin brass.Buying factory ammo,your looking at around $3.00 a shell,depending on the ammo you choose.
All of these caliber's shoot good,and have a good 200 yard range,after that they drop really fast.