The Omega movement 2500C is - in my eyes and after having spoken to many watchmen and read many articles - one of the best mass-produced movements you can get today. It's probably not that rugged in the long term as a Rolex 3135, depending on what you compare (Rolex pivot winding system is weak and prone to damage). Look, probably it will be like this: If you get an average Rolex 3135 and an Aqua Terra with the 2500C (no "lemons", just average units) and you would wear them for 10 years without service, both movements will be quite worn after 10 years and require Service sooner or later. Both. Now, if you really, really abuse these watches, Rolex might be a bit more rugged. If you just use them for normal activities like jogging, biking etc., both will be rugged enough. Let's stop these comparisons. I agree with Georges Z, that Omega might be a bit more delicate than the Rolex (just because the Rolex movement has larger part dimensions), but the 2500C won't be THAT delicate as Georges Z ususally states. Let's stop these comparisons. Both brands, both watches and both movements are mass-produced and high-quality.