Our Malo 41 (really 43'), 24,500 lb with 4JH3TE Yanmar consumes about 1.1 gph at about 2,800 rpm and 7.8 knots with a flexofold propeller. The system is happy at that speed, but 7.5 knots is easier. I don't have the other details handy. Obviously performance suffers in head seas and wind. We see a max speed of 8.5 knots in perfect conditions plowing a huge hole in the water.