In today’s market, steel is the way to go. Almost every steel sport Rolex is impossible to get without getting put on a waitlist. Pieces like the 116500 Daytona and GMT Pepsi even sell for +50% retail price on the grey market. Some AD’s even closed their lists for some models. Same goes with any stainless steel Patek Philippe Nautilus.
In today’s market, the best watches to ‘invest’ in are steel sport models from Rolex and Patek Philippe. Of course, if you manage to get one at retail price. This is of course just speculation. The market could turn of the bubble could burst. The same thing happened to two tone watches in the nineties.