Funny you should ask. I replaced an FSA 30t with a Dimension 28t today and imagine that I hear a faint rubbing (?) sound. The shapes of the two rings looked a bit different so I imagine the chain is a hair closer to the ramps of the middle ring than it used to be. I'll be looking for chainring spacers to move that inner further away from the middle. Eyeballing the three rings they look equally spaced.
Interested in advice from others.