If you have a .416 as you existing largest rifle, I would tend to go to a .500 V-C double rifle. IMO a .450 or .470 while decent choices do not represent a big enough jump up. A .416 bolt, and a .500 NE DR makes a nice battery for DG, the bolt as the backup choice and also very capable for plains game. A bolt action with a scope also is useful for buffalo herd shots, if needed.

For myself, having a .375 bolt action and a .450 No.2 NE dr I would definitely go for a .577 NE as my bigger rifle. For me, can't see the benefit of a .500 over a .450, if a .577 was in the offering. Yep the .500 is far more gun, than the .450, but so is the .577 over the .500. Yes the .577 is a more specialist tool. But if using it on water buffalo, cape buffalo, elephant, scrub bulls, etc, and many a pig, sounds suitable to me.

(btw I also have a ffffing plastic Mauser .404, but haven't used it much yet. Maybe this year.)

Rifle weight? My .450 is a lead pair of pipes and weight 13 1/4 lbs. I carry it all day either in my hands and arms or on a sling. When I first pick it up, it feels HEAVY. Later it feels like a feather ... ha ha, no it doesn't, but I carry it all day in the heat. No blackfella gun bearers here. Fellows grow some muscles.

Ha ha. If I had to climb mountains with it, I might change my mind and get a choice of a lighter one.

Good advice given earlier. Find someone, somewhere and have some shots with some of these choices. If the largest you have shot is a .416, all of the .450s, .470s, .500s, .577s will be serious steps up. BTW no one likes recoil. Some like it less, nothing wrong with that. What is wrong, is shooting a rifle you causes you to flinch. So go for something you can handle. I find shooting something bigger than I usually use, makes the lesser monster feel like a pussy cat. I once found my .30-06 recoiled a lot. When I got a .375, the .30-06 was like a rimfire. Same for the .375 when I shoot the .450. If you shoot a .577, it is a relief to shoot the .450. So you get it I hope.

The biggest recoiler I have shot is a .600 NE.

If considering a Sabatti make sure it has no regulation problems, muzzle griding etc. Many of this brand had a lot of problems a while back. Some owners have fine, cheaper rifles. Some owners did not. Anything being re-sold MAY be being resold for a reason.

BTW Verney-Carron are fine people and make good reliable rifles, with good service. A completely different story. I don't have one btw nor received any benefit from V-C.