Offer him 500, maybe 600 and see how that sits with him. Slingerland, for whatever reason, lags considerably behind the others in value. This is not to say they are not as nice, but the market seems to have always been softer on them than Ludwig and Rogers. Thgey have a deep, resonant tone, the 3 ply shells do, and I like them better, but the market says they are worth less, so be it.