Were you getting those speeds with random reads or sequential? I have one of the Orico enclosures and it works great.
Then I tried 'ATTO disk benchmark'. This tool tries a variety of read and write I/O size ranges. The results I got here were strange. As expected as the I/O size range grows, the read bytes/s increase. Then it hits 1MB I/O size and the throughput drops to almost 0. Write was consistent across the range, perhaps since it simply hits a buffer on the SSD to be processed later.
With dd I achieved good performance transferring a 5GB file, after a reboot to ensure the file cache was definitely flushed.
Perhaps it was an issue with the firmware version for the Orico or the SSD itself. Unfortunately I was unable to update the latter since the 'Samsung Magician' software is windows only. On my windows devices I have no thunderbolt ports.