It offers NOTHING except one less round in the magazine and potential feeding problems associated with ON THE 7mm R M AS DESIGNED a totally pointless and unecessary belt. A legacy of AN OLD FASHIONED American idea that a cartridge wasn't a true "Magnum" unless it was a "Belted Magnum".
Here in Britain we were shooting the 7mm Remington Magnum a half century before the Americans AND in three different styles.
Belted, Semi-Rimmed and Rimless. It's just that we called them 275 Holland and Holland, 280 Ross and 280 Jeffery.
All with a lot more style than the 7mm Remington Magnum. A cartridge that, in real terms, actually offered no real advantage over Remington's excellent 280 Remington of 1957.
It would be, the 7mm Remington Magnum, a lot better if it had been a straight copy of Holland's 275 or in fact the whole "nine yards" and Weatherbyised to be a 7mm Weatherby Magnum.