What year is your MBP?

If it has Thunderbolt 3 (3x faster than usb 3.1) get a TB3 external. I bought a 512GB visiontek for my kontakt libraries. No problems. Runs great. 1700mbps

https://www.amazon.com/VisionTek-Portable-512GB-Thunderbolt-SSD/dp/B07DHDVB1F