Relevance of USB 3 cable length for write/read speed / My Book Duo

What relevance does USB 3.0 cable length have for the write/read speed of My Book Duo? What is the reason why the cable provided is fairly short? Before buying a WD My Book Duo, I am wondering whether a 3 m cable (used instead of the short cable provided) could compromise data rates. Any experience and advice is appreciated.

Hi, according to the specs the recommended size of the cable is up to 3 meters, so it should be fine, however I have not tried this and cannot warranty if its going to work properly.