First, let me say I love both and it's a nice project you have here, even if sometime difficult to achieve as you said.
Opinions are quite subjectives so this is just my personal point of view.
I prefer the 5711 over the 15202.
Why, in details:
1. I think the finishing quality and design is identical between the overall Case+bezel+bracelet. Then, it is just a question of taste and style.
Both are "Sport-Chic" watches but the Nautilus's cursor is a bit more on the "Chic" side whereas the RO's is more on the "Sport" side.
Then, it depends if you prefer a watch with more character (RO) or something more refined (5711).
2. Then we are coming to the Dial.
I feel the 5711's dial is much more appealing and better crafted. I'm not talking about style (subjective) but about the "galvanisation" (don't know the word in English) of the dial. The coating of the dial is much richer when dealing with light colors and relexions than the RO's.
Furthermore, the way the markers are slightly beveled makes the visible work more delicate and soft than the harsh, squared angles of the RO's markers. I don't know if what I say is understandable but put the 2 watches aside and one can compare the smoother look, better finished imho, of the 5711.
3. Then the movement.
I personally don't like the 2121 (nore the 3120). The rotor's rail in the 2121 is something I really don't like in such a high-end watch.
I find it small and less interesting compared to the 324.
Furthermore I find the finishing (cote de geneve, beveling) of the 324 much more appealing.
Only the rotor might be better on the RO.
I'm sorry I'm not really nice with the RO but it is a watch I really like in the style (maybe my favorite) and I tried it several times because I always wanted one.
For a long time, I thought something was wrong and I didn't know what, before the flaws (to me) became clearer.
I'm really comparing both and find the 5711 better (not taking the price into account here). But the 15202 is of course a great watch too.
It's just when I dig into details that I find elements that make me make my choice.
This being said, we can always find a better watch that the one we are looking for. The question is "is the RO able to bring you the pleasure you seek in watchmaking". If yes, whithin your budget, I think it will be difficult to compete with the 15202.
Hope it will help you,
Cheers Dje,
Mark
This message has been edited by Mark in Paris on 2014-02-27 09:04:56