There is actually a number of options for Calatravas in 35mm size... and only you can decide according to your personal choice. For example you mention you don't want something "too old". I would recommend don't take something "dated" which is not quite the same. On the other hand I love beautiful vintage watches which are so classy, timeless, and have an incredible charm that I don't find in modern references. When you say you don't want "something too old" I don't know what is the reason behind: is it a question of design? or are you afraid of reliability? or is it for another reason...? As for 5115 of course it has positive points with its 35mm size and enamel dial; the 215 PS caliber isn't extraordinary but makes the job quite well and is very reliable; as for the design the crown guards (similar to 5107, 5127 or 5125) are really a question of personal taste just like the hobnail bezel. But I am still a big fan of the 570, 5208, 5209, or 565 as I mentioned before

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