The ride was rough and didn't fit the space theme at all. It was just a roller coaster in the dark, kind of; I could see all the supports and other parts of the track, and only the ceiling with the projected stars and planets (that I found really cheesy, Disney can do better than that!).
The one in Disneyland circles around the building and gets up some pretty good speed, the track is almost invisible, so all you see is stars and glowing rockets (the other cars with blacklight reactive paint) zooming around.
Needless to say, I've only ridden Space Mountain at MK once, and I don't have the desire to ride it again until it's changed.
This is SO us! We LOVE SM at DLR. The track is very twisty with lots of circling and curves. In fact, we saw the model for the ride in the 50th anniversary exhibit and I would be afraid to ride it if it wasn't so dark. You are literally inches away from the track above you on the whole ride once you exit the loading area and the initial hill. The ride is pitch black and the music is great. You can't see your hand in front of your face and it is exhilirating!
DH and I rode SM at WDW on our last trip and couldn't believe how bright it is on the ride. It was so boring being able to see where you are going the whole time. It's sort of a kinda dark, not very exciting roller coaster in a big building.
The rehab in January is scheduled to replace all of the track to make the ride smoother and to darken the building so there won't be as much visibility. As far as I am concerned, it is a MUCH NEEDED change!
)
All I can remember is that weird rushing sound when you get to the end.
But hey its their choice if they want to change it or not. 
