Raising the rear hub (lower hole) will give the car a bit less rear grip, but it will lose traction more gradually. If the rear hubs are too high, the car will be loose everywhere, and if they are too low, the car will feel edgy as traction will be inconsistent. It will have more traction up to a point, then lose it suddenly. If you raise the rear hub, for example, go 1 hole higher on the rear tower to keep the roll center similar. Arms and drive shafts parallel at ride height is a good base.

Raising the front c-hub (lower hole) will make the steering less responsive. It will have a little less front end grip and you can drive the car harder. This is mainly used on rough tracks or tracks with aggressive traction, like the 2012 Worlds. Lowering the front c-hub will give the car more steering and it will feel more aggressive. This is used on small, clay tracks where the track is smooth and consistent.

As always, make sure to readjust your droop and ride height after making these changes so the results will be more clear.