What .470 ya got? I bought a Merkel a few years back and quite like it.
A PH I hunted with last trip brained a problem elephant, who was trying to climb in the truck with the 3 of them, at 5mtrs with a .470 and a Woodleigh 500 gn SOFT. He meant to use the solid in the other barrel but pulled the wrong trigger in all the excitement and killed him stone dead with the soft. He was impressed as was I.
I think the next double will be a Heym in .577, not sure why but my rationale has never been why, it's always been why not?