Good news: very neat, immediate recognition by iMAC, read disc OK
Bad news: eject mechanism faulty from start. Mechanism worked OK with no disc present, but would not eject if disc in tray. Tried several discs, same result each time: had to resort to paperclip in "emergency eject" hole each time. Even then, wasn't keen to give up the disc!
Returned to Amazon, no problem there. Trusting it's a one-off, have ordered a different model Samsung as replacement.