IMO, for the guys that liked to buy big guns and shoot them little, I suppose the 300 Ultra stole some of the SEVENMAG's thunder a few years ago.
But I don't see many new 300 Ultras around these days.
7mm Rem Mag is one of the rounds I shoot/hunt with the least. I usually hit right on either side of it (7 STW or 280).
But I would probably be the last to go if I had to start selling.
When properly hand loaded, it is uber versatile.