Still having super slow speeds with USB 3 flash.

Just upgraded to
OpenBSD 6.3-beta (GENERIC.MP) #34: Tue Mar 6 07:52:30 MST 2018
deraadt@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP

everything still fine.
whole process took about 10 minutes (via http)

Jan