Gold vs Silver vs White...

[ragwo]

So... if Golds are simply Silvers, pushed harder, does it stand to reason that they should have poorer longevity over time?

Are you referring to the old Phantom Gold or the 108dB? The Golds have a titanium tweeter, the Silver has an aluminium dome. The internals are not the same if I remember correctly. The 108dB has the ADH-3 amplifier module, and a faster and more power efficient SoC. So the Gold and 108dB aren't a Silver pushed harder.