I just did a quick comparison of testmy.net and this speedtest.net.
I am supposed to have 15/2 speeds I think but this is what I got which is kind of the reverse of what I expected (I thought testmy would be lower than speedtest).
testmy.... 9884 download, 1764 upload
speedtest.. 9468 download, 1763 uopload
optimum site's "test" 12600 download, 2500 upload