I've just noticed that if you use googles speed test service, and navigate away from the tab with the speed test on (say to check another site) The download figure is reliable, but the upload seems to always report 0.08mbps.
If you run the test afterwards, but remain on the page it gives a reliable upload reading.
So may be that some internet issues are misdiagnosed as poor upload speed because of the speed test? Just something to consider.
Different speed tests can provide varying results but I wasn't aware of this bug in particular - definitely something that's worth being aware of when trying to diagnose potential broadband issues. VM generally recommends speedtest.net for the most reliable speed-test results.