I'm using a 2014 MacBook Pro Retina with El Capitan OS with X-Plane 10. The only sims avionics which work flawlessly for me are the Cessna 172 SP, 182RG, and the Mooney M20 T. All the others: Cessna P210, Phenom, Piper Lance II (v9.7), Super Viking, X Multi PA31, Angel 44, Baron B58, Cirrus the jet, Eclipse 550 2-0,, Falcon 7X_v9_510r2, Gulfstream G4 SP_V10, Hawker, Meyers 200, Columbia 400, Beechcraft 2000 Starship, Bonanza Vtail, Cessna Citaton, P180 Avanti Ferrari Team, Avanti II, SkyrocketII, and Mooney M20K 252 Encore have avionics and APs which don't work, or work intermittenly.