Internet speed

I just upgraded to Preferred High speed 25 x 5. my cable modem is a docis 3.0 Netgear CG3000D. Using the Cox speed test I have NEVER got 25 x 5. I get 9.47 x 7.91, 14.11 x 11.56. Using www.speedtest.net, I get 30.49 x 6.78. Has the upgrade to my account been completed. to preferred w/speed boost? What about firmware for the modem?? Which is the reliable test??