I don't think they're going away completely.

You're probably right to think that the gold buffalos will take a pretty good part of the Gold AEs market share but I kinda doubt that the Gold AEs will go away completely. There are quite a few people that like the gold eagles that will either stick with the eagle or collect both. Also, the gold buffalos are just that, gold. I'm not aware of any program to expand them into silver or platinum and until that happens the silver and platinum eagles will still control that portion of the market. Personally I'm a fan of SAEs and I'm working to build my set of them. They started making them the same year I was born and I'll be ticked if they get rid of them.