OPA855: Unity gain frequency of OPA855

The unity-gain bandwidth and GBW are similar, but the GBW is usually measured at a different frequency.

A decompensated opamp like the OPA855 is not guaranteed to be stable at unity gain. As shown in figure 10, the unity-gain bandwidth would be at 8 GHz if the straight line would continue below 15 dB. But it does not, so it does not make sense to talk about what happens at 0 dB.