Where would it be cheapest to buy legitimate expensive watches?

I’m looking to buy a IWC watch. But where would it be cheapest? It’s made in Switzerland, but might be cheaper in Hong Kong or elsewhere.

Contries, places, shops (non internet, though suggestions are welcome) etc. – all suggestions are welcome. The question is not only related to IWC however, but rather where luxury goods like these are actually cheapest. Any customs and fees when returning to your own country are not relevant in this regard.