Not sure if this is direct experience - I’ve had an Osymmetric on my Di2 bike and an absolute black on my mechanical bike. Di2 bike used the DA9000 FD and mechanical has R9100 set up front and back. it seems the ability to micro adjust with mechanical groupsets yield better results with oval chainrings. On my Di2 set up if I’m not careful with shifting the chain will definitely drop whereas with my mechanical set up I’ve yet dropped the chain.