I have FSA Gossamer with 105 on one bike and Dura Ace 7800 on another. With all due respect, the FSA does, in fact, have a full set of tooth ramps and channels on the inner surface of the large chainring. There isn’t any noticeable difference I shifting between the two. As to any difference in rigidity, as I weigh 150 lbs. in the dead of winter, I’m not the man to ask.