Of course the most obvious difference between an authentic and a replica Breitling watch is precisely that, an authentic watch has been produced by Breitling master craftsmen in Switzerland, whereas a replica has been manufactured in one of many other countries, often the Middle-East, South-East Asia or Greece/Turkey.
The next greatest different between a replica and an authentic Breitling is the inner workings of the watch. The movement in an original Breitling is the result of many years of testing and experimenting to ensure that the watch delivers the most accurate reading of the current time. In addition to this, the movement of a real Breitling is also designed to retain its accuracy in a variety of environments, from the desert to underwater. A replica watch movement will however usually be mass produced, this is not to say that it will not have the same, or near similar resilience to that of a breitling superocean heritage replica watch, but it obviously will not be of the same quality and the components of the mechanism may develop faults at a quicker rate than that of a genuine Breitling mechanism.
However, beyond analysing at the inner components of the watch, a replica will be made of largely the same materials as that of a Breitling in terms of the other factors which make up the time piece, for example the strapping and the case. Whilst many years ago replica Breitling watches were largely seen as uncomfortable pieces nowadays much effort has been placed into ensuring that the strapping of any replica is true to the original in both look and feel.
By way of a short conclusion then, without including the inner workings of the watch mechanism, there is actually very little difference between a breitling superocean replica watch and the real article and therefore if you find yourself unable to afford a genuine piece then you should seriously consider acquiring a replica as nowadays you will find that they are not only very similar to the real item in design, but also in terms of the materials used to construct the watch.