As others have said, if your in a position to buy a gen at such a young age my advice would be to go for it and hang on to it for life. When I was 21 I bought a gen datejust and a seamaster, but I proceeded to chop and change them over the next few years. This was fun at the time as I owned countless gens from Omega to Graham and everything inbetween, however as life started getting complicated (Kids, Cars, Mortgage, Wife, Wedding etc) the watches were slowly downgraded, I went from Rolex/Omega on to Seiko and micro brands such as Helson. Then when I needed funds for a business venture I sold everything and bought a rep. Now I have a few reps and im still happy, but I often think that I should have held on to those first couple of gens for life.