If I knew that, I would buy them now. If I had the money there are many knives that I would buy, but not to collect them. I do not collect knives, I buy them to use them, so in 15 years I hope that I have purchased a lot of knives that I have gotten great use out of. If that is the case I will have gotten what I wanted out of my knives. If they have been a good knife then I really don't care if they have any resale value in 15 years. They will be carried with pride.