I can confirm these fiber lines will cut through wire rng guides and chrome finished ring guides. Even saw a roller guide where the roller wasn't rolling free that had a cut in the roller. In the past five or so years that I've been using these lines I have not seen any problems with the line cutting a ceramic ring guide.

As for cutting the guide on a level wind - I have never seen this but would guess it is possible. I've used a Penn 109 for several years with Power Pro line and haven't seen any cutting of the level wind guide.