As a fairly simple man I've never fully understood why we should change somthing that works perfectly well? Our women change things around all the time, and thats enough for me...;) Stick to the woodleighs, they're great bullets and far good enough. A lot of PH's say they're splendid bullets, and as far as PHs goes I'll quote R. Ruark, he said something in the neighbourhood of: "...what's good enough for the pros are good enough for an amateur like me..."
I have a Merkel DR .470, and I'd never ever put anything through it that might harm it, nor overload it. Frankly I don't think a buff or a lion would care if you used woodleighs or swift in a .470, there are noe mammals on the earth today that don't succumb to a solid or soft woodleigh from a .470... My two cents though..