I don't understand what you said. Any file from that site is fine. Preferable one that takes 10 mins or more so you can see if your speed drops.
Some ISP's have special programs that can detect p2p sharing programs. They will filter that person's bandwidth for that p2p program. So they only get slow speeds. Here's an example of how a p2p bandwidth shaper can work against
Gnutella network:
Bandwidth Shaper Sample - typical of how some ISP's use it (click on link) ie: giving priority to net surfing & low priorities to p2p sharing.