Need some recommendation/help choosing between three watches. I'm looking at picking up either a used Rolex Air King (114200) in stainless steel with a silver face, the Omega Speedmaster Moonwatch 50th anniversary edition with brown leather strap and 1861 movement, or the Zenith Pilot Big Date with an El Primero movement. Budget I'm trying to stick around is $3000-5000 and I have a soft spot for watches tied to aerospace (as you can probably tell). While the Air King is the odd man out I like that its a 114200 and thus in the chronometer territory. It's also a very versatile watch that would fit any occasion and likely maintain value the best. The Omega really hits the aerospace soft spot with its proven track record in NASA/Space. While I would ideally LOVE to find a vintage model with a 321 I'm not knowledgeable enough to look at a vintage movement and deduce how well its been maintained to properly evaluate it without letting my soft spot override my other sensibilities. At the top of the price list is the Zenith. I really adore this watch's face and the El Primero movement overall, but I do worry that it and the Omega won't be great everyday watches due to their size and weight. I also worry about buying this watch from the grey market the most as I see the Rolex and Omega as much easier to find parts and experienced watchmakers for while I worry the Zenith would be better off purchased from an AD for direct service from Zenith. Sorry for a bit of a long winded request but any thoughts about these three would be greatly appreciated. This is my first non-ETA (if you don't count the Omega) purchase and I'm finding it very hard to choose between them.