As someone who eats, breaths and sleeps videogames, I can honestly say that DisneyQuest is a failed concept. The technology behind most of the simulators is constantly updating, so much so, that the "rides" they have there are laughable. Anyone with a PS2 or GameCube will have better graphics and interaction that anything seen there.
Being here in Chicago, I visited our DQ before its demise, frequenting it only for the Dance Dance Revolution machine.
DQ did not have the Disney feeling. It has always felt as is some outside source built them, and Disney just tried some color schemes to attempt to give it the right feel.
I would not be sad to see DQ go, although I think a permanent museum in its place would be an excellent idea.