Tax free shops in the international airports are always a good place to buy luxury items because of the exemption of TAX. However, you may be limited by the purchasing time or the availability of the watches that you like.

If you are not a resident in the UK, luxury watch shops in Britain might be the best place for you to buy a genuine Rolex watch. There are two reasons for it: 1) Due to recession, shops are keen to give you a big discount, which is usually around 10-15%, 2) On top of that, you can get VAT refund if you are a visitor in the UK, which is another 15-20% off the purchasing price.

There are many luxuary watch shops in big cities like London, Edingburgh, and etc, so you can shop around and get the best deal.