Hello,
f you are planning to host heavy files or media, download speed becomes an important critera for host selection. Download speed in fact can be affected by a number of parameters : location / country of the host and the user, connection speed at host's datacenter, traffic /load on the particular server, maximum port speed of the server and of course the connection speed of the user. But the bottom line is, the user is only concerned about the download speed he is getting and so you should actually be downloading something from the server to test it.
Thanks.