Is the glass original? A new building would have much improved glass than Union Carbide's old glass curtain . Better configured rest rooms, elevators. Higher ceiling heights. Chance for terraces. Lots of good reasons to replace. I mean how different is this building from Seagram's and several others? OTOH I understand nostalgia. Buuut, I don't think that is enough. Wouldn't be enough to sway me, if I was Jamie Dimon