Here is my humble experience for 1~2 weeks running unRAID 7.0 Beta 2
I'm running QNAP TL-D800C enclosure with 8x12TB drives and ZFS at 93% usage, pushing 400mbit/s out just about NON-STOP. 0 drops of that enclosure or any of the drives. 0 errors from the drives.
On the other hand I have metric ton of issues booting the unRAID USB it self ( using Samsung BAR Plus drive in USB 2 port as recommended ), with the damn "waiting for UNRAID device to come online" or whatever is the message. Go figure...
My 2c.