SpeedOfMe reflects the actual speed that you are experiencing via the browser. Here's how you can make sure:
Try downloading one of the larger sample files (e.g. samplefiles/sample131072k.bin) directly from the browser and watch the download speed. (In Chrome use this address to view downloads and their actual speed: chrome://downloads/ ).
It should be something close to SpeedOfMe measured speed.
Please keep in mind that browser download speed is usually based on Megabyte/s. So you need to convert it to Mbits/s (multiply it by 8).