BIG_GREG....BIG difference between a Grey Market Amp and an Amp with No Warranty. If your not the original owner BUT the amp has your country’s voltage and was purchased in your country they will still fix the Amp and charge you for it. If you purchase a GREY MARKET amp they will refuse to work on it PERIOD. Thats a HUGE factor to consider.
That's not necessarily true and will vary from manufacturer to manufacturer. I have more familiarity with this issue as a photographer. For example, if you buy a Canon camera from another country (international or "grey market"), Canon won't honor the warranty. They will repair it. The same holds true for many products. I've never heard of a manufacture refusing to repair an item because it was an international model. It seems unlikely, since Gryphon is not made in the U.S. Have you contacted them and been told that they won't perform repairs?
There's also the option of having a local repair center make any needed repairs. Is there something proprietary about their amps that would force you to ship it to Denmark rather than have a local (or at least US based) dealer service it?
I agree that the seller should have been forthcoming with those details in the ad itself, but I'm having a hard time understanding how it's a "Deceptive add" (SIC).