I had a SEGS graded Mint State 1848-C quarter eagle when I was a dealer in the late 1990s. I had it on consignment. It was over 25 years ago so I don’t remember all of the exact details, but the coin was nice. Another dealer also had an 1848-C in a PCGS holder that had the same grade. The PCGS coin was slightly nicer, but it was very close. The big difference was I was offering my coin for $6,500. The other dealer wanted $20,000 for his. I sold the piece at a Bay State show in Boston to Bowers and Marena Galleries, one of Dave Bowers’ earlier partnerships. I can predict that the coin did not stay in the SEGS holder for very long.
I still have 3 SEGS coins in my collection. I feel they would cross but I don't see a reason to ever do that. Each coin still has a special meaning to me from long ago. One of these came from one of Jeremy's charity auctions. A few here probably remember those auctions. It was a great feeling to pay crazy money for a great cause. In today's times, I believe very few SEGS coins would cross or upgrade.