What Hub model do you currently have? If its a SH2, then on upgrade, you have to switch to a Hub3. If you are internet gamers that is a perilous step. Out of interest why do you want to upgrade ?
-------------------- Services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.
Unless you are a very keen gamer or have several users downloading video at the same time, there is no point in going for the fastest speed. You won't notice the difference from 200 Mb except in your bank account.
Remember that the servers you download from have their own speed limits