I have owned two Omega models with the AR coating on both sides of the crystal and one model with the AR coating on the inside only. Having the coating on both sides substantially reduces glare and reflections but the exterior AR coating, while quite durable, can be scratched. When this happens, you have three choices: live with the scratch, remove the coating or replace the crystal. In models with the inner coating only, there is no risk of picking up a scratch, but glare and reflections are significantly increased.