Is it unnecessary to unmount twice?

My Android 4.0.4 tablet (Onyx Boox i86) mounts the internal and external SD cards as real read/write drives (not MTP) on my computer. In order to do this it goes into "USB mode" where the tablet's OS no longer has access to the storage while the computer is accessing it. Before unplugging the tablet, I usually do "Eject" in the desktop OS X/GNU/Windows file manager, and then click "Turn off USB storage" on the display of the tablet. Is it alright to: 1. Just eject the drives on the desktop, and then physically plug out the cable? 2. Just click "Turn off USB Storage" on the tablet display and then plug out the cable?