I've so far had pretty good luck with these:
https://www.bestbuy.com/site/crucial-x6-se-2tb-external-usb-c-usb-a-portable-ssd-black/6457934.p?skuId=6457934
Got one in the car for a little over a year now and recent got another that's plugged into our new TV in the living room with concerts and misc. videos. I put some Velcro on the one behind the TV and it's nicely hidden back there.
Can't say I've ever seen the transfer speeds (800 MB/s read/write) ever max out with anything but not the worst. I want to say the fastest I've seen big transfers (10+ GB) go is in the 400-600 MB range but I can't remember right now. Short 2+ GB are blink-and-done though.