I won't use the pen set as it appears new, and I have other pens.
I am first and foremost a watch guy, and when I saw the estate sale photos I knew I had to snag the set because of the Omega connection. Just learning about the set has been worth the six bucks I paid. I will put the set into my box of Omega stuff and forget them.
At any given estate sale or auction I look first at the watches, and then at knives, pens, musical instruments, and even yo-yos. I have collected Bucherer Rolex spoons for a few years and I now have about 160 of them, never paying more than three bucks each.
If you have a good eye you can frequently pick up something a seller either missed, or that they knew nothing about. As Emil Faber said, knowledge is good . . .