ystem-Product-Name:~$ software-properties-gtk 
franco@franco-System-Product-Name:~$ software-properties-gtk 
mirror: archive.ubuntu.csg.uzh.ch - time: 0.22443628311157227
mirror: mirror.switch.ch - time: 0.24463391304016113
mirror: mirror.23media.de - time: 0.27188706398010254
mirror: ubuntu.ethz.ch - time: 0.2777748107910156
mirror: ubuntu.fastbull.org - time: 0.33737874031066895
mirror: lug.mtu.edu - time: 1.008972406387329
mirror: ftp.cs.mun.ca - time: 3.820878267288208
and the winner is: archive.ubuntu.csg.uzh.ch