http://www.chrono24.com/audemarspiguet/royal-oak-offshore-navy-blue-mens-chronograph-42mm--id4927542.htm
It is based on a real model as the link I've posted shows. Replicas are never A++++ Swiss made, indistinguishable from genuine no matter what anyone tries to tell you. They all have slight differences and knowing them, understanding them and working to fix them can become both very satisfying and deeply annoying.
Examine the two links, open them in separate windows and see what differences you can spot. The date window is in a slightly different position and the hands are slightly different. In the end it comes down to what you can accept and what you can not tolerate.
It would be be worth doing some reading of threads in the AP section. Some of the guys have built amazing frankens using genuine dials, hands, crystal and different movements, but the cost can get eye watering.