I've ran it multiple times in Chrome only and got vastly different results just there, from 200 to 600 down on a 500 connection. Must be heavily dependant on moment-to-moment network conditions I guess, to the point where it's nigh useless.
Yes, the bandwidth test is so short that I'm not surprised it gets inconsistent results. I'd wager the speedtest.net being longer was not decided for fun, but to get more consistent results.
edit: Now I realize that the later tiny-small-medium filesize downloads also add to your above-the-fold download performance, so the results of the initial warm-up test are discarded later.
