They are fast no doubt but it's not enough speed to blow past GW. We are the perfect mixture of size and speed. And in order for speed to burn you it has to get past the second level or have time to throw.
They definitely have speed, to say the least. Another thing you should factor is that GW hasn't seen good speed overall as a team this year, let alone the premier speed in 1A. Not saying GW isn't fast (I know they are), but compared to teams they have played this year, they look unrealistically fast. I would have loved to see Graham/GW play and see how GW would have adjusted to the speed. I don't think Sussex is there with Graham in speed overall, but they aren't far behind.
However I am sticking to my pick of GW. I don't believe (after watching a little film) that Sussex will be able to run the power out of the shotgun on GW's line. To me, GW doesn't want to see the athletes of Sussex make any plays on D. Stick to dive/power/iso/trap (whatever you want to call it) and ride the hogs to the win.