If the enclosure only supports USB 3.0 or 3.1 Gen 1 then you are limited to the USB 3.0 bandwidth of 5GB/s (less than SATA3 6GB/s), but USB 3.1 Gen 2 connections support up to 10GB/s, so you will only get the max of 6GB/s due to the internal SATA3 interface in the enclosure.
So if you want to get the best, make sure it's got a USB 3.1 Gen 2 Micro-B or C connector