[cturner]

"The only difference is how it presents itself to the switch (ie, says its a Cisco optic), not actual difference in performance."

That's not the only difference. I have had situations where I ran equivalent optics side-by-side, and then touched one and it was hot, and touched the other and it was not hot. They do contain different components. In the case of that test - the atgbics SFP was cool, and the other clone unit was hot. My dealer was able to get me in contact with someone technical at atgbics (the cool-running unit) who explained the difference, "The DSP might be say 13nm where more modern more expensive ones are 5nm."

But you definitely do not need to pay for "genuine" optics to get high-reliability optics. You just need to shop around the clones - atgbics is a clone.