Your 'old Eizo' probably has lower contrast than that announced.
Manufacturers announce the contrast without uniformization system and in the best case. They also inflate the numbers a bit. But when you test it in real world, it always give lower values.
The uniformization system always lowers the contrast quite a lot because of the way it works. But what matters is that it's much more desirable a uniformized screen with 'low' contrast than a non-uniformized with higher contrast.
The problem is that we cannot measure the real contrast of the SW270C because there's no way we can deactivate the uniformization system.
Can you tell me which EIZO exactly is, so I can search for real values?
Anyway, 1:740 is not that much below 1:960. You have to remember that is a geometric scale, not arithmetic. That means the SW270C is 9.5 steps and the EIZO 9.9 steps. So the difference is about a 4%. Not that much, huh? ;-)