You might have seen the auction for KOF 99 and 2000 on ebay by this guy named Indonesian (by the way, I have done business with him before, he does a great job). According to the page, the suggested price for KOF 2000 was about $370; the auction went for $580. Hope that helps.
I would pay 380.00 but that better not start a trend. I don't want to dish that much out next time if there is a next time on new games. If Last Blade 3 or any other game comes out and they charge this much I will be finding a different hobby. 260.00 is pushing it.
I find anything above $400 for a new Neo-Geo game that may or may not increase in value to be a bit hard to swallow. Hopefully NCS will follow tradition and sell the game at $270, just as they do all other new Neo-Geo releases. Expect Buy-Rite and other, shadier Neo-Geo dealers to price gouge for as much as they can possibly get away with.