The early Winchester solids were not all that solid. One gets the impression they are not all that much better today since there are so many hand loaders using other bullets.
I have an acquaintance who bought a box of Winchester loaded 458 cartridges with solids and found the solids had no cores, just the empty jackets. That sort of thing does not enhance the 458's reputation.
With the powders and bullets available today the 458 can do a decent job but still suffers from a case that is too small. Here in the USA we suffer from magnumitis and insist on getting the maximum possible out of a case. This is putting the cart before the horse. The sensible approach for a dangerous game cartridge is to first determine the required ballistics and then choose a case that will deliver them with low pressure. Something the Brits understood well.
