i dont have a 480, but here is how i see it as a reloader. the 480 will handle a heavier bullet than the 44. 400 grains seems the standard. with the 44, the heaviest i have is a 310 grain; the heaviest i know of is garrett 330 hammerheads (designed for redhawks only). my 310 gr. chambers in my 44, i dont know if the 330's would. i dont know what kind of velocities one might get form a 480 lever; but that 400 grain bullet should at least be doing 1100 - 1500 fps? comparable to 45-70 power, in a shorter cartridge.
considering that these guns are designed as close range weapons, i dont know how much more lethal the 480 might be. but it definately uses a bigger hammer to pound the nail. given the price of components, though, i will stick with my 44's.