Great watch and one of the few Omegas that has always captured my heart and interests. Also, great reading about how you came to make your decision. It is truly an iconic watch, and a tremendous value. It is a quality piece that should give you many years or decades of enjoyments! At some point I might add one to my own collection. I think its history and price are great reasons for choosing a Speedmaster. However, I would suggest that NASA's tests while relevant in the 1960s, are today little more than a historic footnote and have no bearing on the modern Speedmasters or Daytonas. While the classic manual wind Speedy Pro is very close to what went to the moon, its movement and bracelet are not the same, and avid collectors prefer the original with original movement. Furthermore, the Daytona is about as far from the Daytonas of the 1960s as a Model T Ford is from 2013 Ford Mustang. The movement in the 1960s Daytonas was a manual wind Valjoux. By 1988/89 the Daytona movement was an automatic, based on Zeniths El Primero, but highly revised, and by 2000/01 the Daytona's movement was a completely in house automatic movement with a 72 hour power reserve. In addition, the case, bracelet, dials, etc are complete different, and even as of 1988/89 the Daytonas were far more water resistant (100m) than Speedy Pros. As for prestige and fame, its relative and depends on how its measured. Yes, the Speedy has been to the Moon, its been around for longer than the Daytona, and its a very important piece of horological history. However, the Daytona is iconic in its own right, as a watch chosen by race car drivers, the most famous being Paul Newman, Jackie Stewart, and Hurley Haywood. For nearly 20 years it was "THE" sports watch to own. In all steel it was so highly sought after that for nearly 15 years, most AD had waiting lists that were years long, and if one could buy one at list price it could easily be flipped in 24 hours or 5 years later for a profit of between 50 and 100% depending on where you lived...and that's not even considering auction results of vintage models. So I'd say they are at least equally famous and prestigious, but different. I think the Speedy Pro is a fantastic watch, I love its history. However, if one is comparing the modern versions, the current Daytona is a bit more practical (auto with 3 day power reserve), more water resistant, and more rugged. Today there are modern Speedies that are more rugged, practical, and competitive with current Daytonas, but those lose their historic significance. I just think you have clarify that today's watches are quite different from that which was offered by in the 1960s, and hence NASA's choice might not be a reason to make a choice, other than it adds to its historical significance. I really love both watches. In the end there is no wrong answer when it comes to choosing between them. Buyers of each will walk away with smiles on their faces and feeling like they made a fantastic choice!