Zend certified PHP/Magento developer

SSD Latency over USB

I’ve just learned that (internal) SSD latency is in the ballpark of some microseconds (1/1000th a millisecond) and HDD latency is in the range of milliseconds.

I went out and bought a USB-C 3.2 Gen 2 SSD to take advantage of the drop in latency. But I can’t find an answer online regarding how connecting over USB might make an impact.

I’ve read posts claiming SSD latency over USB is a few milliseconds, and some others which claim it’s still in the microseconds. Given that using external SSDs as boot drives is reasonably common, I hoped there would be some reliable discussion on the topic, but I haven’t been able to find any.

Is anyone aware of a possible approximation/guess about external SSDs’ latency?
Is it still in the microseconds, or is it longer?

Please cite your sources if it’s not much trouble, or not.