I'd guess fuel consumption 30gpm at 3000rpm
While looking at boats to purchase that had these powerplants I did some asking around and came up with the info that they're great motors but replacement parts are expensive and not as commonplace as most while searching for them.
At those low hours if the boat really appeals to you I'd say "jump on it". They're sure to have plenty of life left in them prior to any major reconditioning.
I'm one of the optimists that thinks the economy is truly rebounding and the low prices for boats of this caliber will soon rise again.
Just bear in mind that all my info comes from one performance boating buddy and all my internet searches for answers.