I did some tests. For file transfer by ethernet I get about 100 MB/s or 800 Mb/s, close to the rated 1Gb/s. But for Time Capsule backup by ethernet, speeds range from 10 to 30 MB/s; and by wifi from 1 to 9 MB/s. Now to backup 1TB at 9MB/s we require... 31 hours. And at 1MB/s we require over 11 days.