We've seen several in the stupid-expensive category over the last year that I've been here. Toggles and bottom-adjustables are rare, yes. And if someone is stupid enough to pay that price, then we'll all be wrong about the value estimates of rare razors. Me, I can't see that razor being worth over $250, and really I wouldn't pay that, so I suppose I don't think it's worth over $150.
from the wiki:
date code with year and quarter" F-4 1960 4th quarter, underside, and bottom:
from ebay:
date coded F-4 but I am told this does not correspond with the Gillette date codes exactly and it is safe to say this razor was sold in 1956