Well the saying that has been said before that Rolex makes the most expensive $500 watch... In the end Rolex is a mass produced watch with a mass produced movement. There has been many comparisons between the 3135 and the 2892, which is in my Victorinox DM 500, and the conclusion is both are very good movements. IMHO if movement experts can't declare an overwhelming difference between a mass produced in house movement and a mass produced outsourced movement then it's a draw, especially if there is over 5 time price difference (Considering the price on the street of a 3135 at about $2000 and the 2892 at $350)
Rolex does yes, bu AFAIK Omega still requires significant support from other ETA subsidiaries to make their movements. The 8500 was designed by Omega but they had to get significant support in the production from Nivarox and ETA, the CEO publicly said he wouldnt call it an in house because of the help from outside of Omega.
Just my opinion, but the magical appeal of companies (not just watch industry, I'm comparing the cycling industry also) using in house components is that it is an excellent way to muddy the water as far as the consumer being able to do price comparison. If the comparison is not easy for the consumer then it is far easier for the consumer to be duped by the "marketing" efforts of the company. Marketing is a way for a company to get the consumer to pay a premium for the intangible.