To clarify, the C hub tower change is usually done along with the use of a dremeled down U brace with 0-1mm of washers under the Ballstud.

Switching to the C hub tower without shaving the ubrace will lower your roll center.

Switching to the C hub tower and shaving the ubrace will raise your roll center.

You can achieve a similar feel with the A hub towers and running 0-1mm washers on an unshaved ubrace, but the feel will be slightly different.