Number count, and condition.
Love my SCs, but there are fewer NIs, and then, the heavier, softer brass baseplate frequently reflects bent teeth from dropping ... and collectors (ahem) are picky. Having busted "teef" off a NI trying to straighten, I nowhave a perfect one ... and rarely use it. Don't want to drop it. Gatsby probably bought another when he bent a tooth!
SC is a great shave and the razor may be less elegant, but more durable. IMHO.
EDIT: here's one for the bravest:
AA
Love my SCs, but there are fewer NIs, and then, the heavier, softer brass baseplate frequently reflects bent teeth from dropping ... and collectors (ahem) are picky. Having busted "teef" off a NI trying to straighten, I nowhave a perfect one ... and rarely use it. Don't want to drop it. Gatsby probably bought another when he bent a tooth!
SC is a great shave and the razor may be less elegant, but more durable. IMHO.
EDIT: here's one for the bravest:
AA