Data gathered from boattest.com.
Malibu Wakesetter LSV with 340-hp Indmar Monsoon 340
http://www.boattest.com/boats/1720/test_results.aspx Test Power: 1 x 340-hp Indmar HammerHead 383
RPM MPH Knots Total GPH MPG NMPG Range NM Range dBa
700 4.8 4.1 1.0 4.95 4.30 245 213 N/A
1000 6.5 5.6 1.6 3.92 3.41 194 169 N/A
1500 8.3 7.2 2.6 3.14 2.73 155 135 N/A
2000 10.8 9.3 4.3 2.51 2.18 124 108 N/A
2500 12.7 11.0 6.0 2.12 1.84 105 91 N/A
3000 24.4 21.2 8.2 2.95 2.57 146 127 N/A
3500 30.8 26.7 10.3 2.97 2.59 147 128 N/A
4000 34.2 29.7 13.4 2.56 2.22 127 110 N/A
4500 37.9 33.0 17.5 2.17 1.88 107 93 N/A
5000 42.2 36.7 22.2 1.90 1.65 94 82 N/A
5500 44.6 38.8 32.3 1.38 1.20 68 59 N/A
MasterCraft X-30 (2006-) w/ 1 x 350-hp MasterCraft MCX
http://www.boattest.com/boats/914/test_results.aspx Test Power: 1 x 350-hp MasterCraft MCX
RPM MPH Knots Total GPH MPG NMPG Range NM Range dBa
600 3.9 3.4 .9 4.33 3.77 238 207 67
1000 5.7 5.0 1.5 3.80 3.30 209 181 68
1500 7.6 6.6 2.7 2.85 2.48 156 136 68
2000 9.1 7.9 4.8 1.92 1.67 105 91 72
2500 16.7 14.5 7.3 2.30 2.00 126 110 78
3000 23.7 20.6 9.5 2.49 2.16 137 119 79
3500 28.8 25.0 12.1 2.38 2.07 131 114 82
4000 33.2 28.8 15.4 2.16 1.88 119 103 85
4500 37.0 32.2 20.1 1.84 1.60 101 88 85
5050 42.3 36.7 26.7 1.58 1.38 87 76 87
Yamaha 212X 2 x 160hp engines
http://www.boattest.com/boats/1742/test_results.aspx Test Power: 2 x 160-hp Yamaha HO
RPM MPH Knots Total GPH MPG NMPG Range NM Range dBa
1600 3.1 2.7 2.6 1.18 1.03 53 47 72
2500 4.8 4.2 2.4 2.00 1.74 90 79 74
3000 5.6 4.9 2.7 2.12 1.84 96 83 75
4000 6.5 5.7 2.9 2.28 1.98 103 89 80
5000 7.4 6.4 3.8 1.93 1.68 87 76 83
6000 12.1 10.5 6.2 1.95 1.69 88 76 85
7000 27.5 23.9 7.8 3.50 3.04 158 138 88
8000 36.2 31.5 11.0 3.28 2.85 148 129 92
9000 43.3 37.7 14.4 3.00 2.61 136 118 98
10000 51.3 44.6 18.4 2.78 2.42 126 109 98
11500 52.9 46.0 21.3 2.49 2.16 112 98 100
SeaDoo 230 Wake
http://www.boattest.com/boats/1464/test_results.aspx Test Power: 2 x 155-hp BRP 4-Tech
RPM MPH Knots Total GPH MPG NMPG Range NM Range dBa
2000 5.0 6.9 2.6 1.92 2.65 69 96 73
3000 6.9 6.0 5.1 1.35 1.18 49 42 81
4000 8.6 7.4 5.9 1.45 1.26 52 45 84
5000 27.8 24.2 8.4 3.31 2.88 119 104 86
6000 39.7 34.5 13.9 2.85 2.48 103 89 84
7000 50.5 43.9 20.0 2.53 2.20 91 79 92
7400 52.6 45.7 21.3 2.47 2.15 89 77 94
Test Power: 2 x 215-hp Rotax Supercharged 4-TEC
RPM MPH Knots Total GPH MPG NMPG Range NM Range dBa
1800 3.5 3.0 1.6 2.16 1.88 103 89 68
3000 6.4 5.6 3.6 1.18 1.58 87 75 74
4000 7.5 6.5 6.5 1.16 1.01 55 48 81
5000 17.0 14.7 10.6 1.61 1.40 77 67 87
5500 26.2 22.8 13.3 1.97 1.72 94 82 88
6000 34.6 30.1 17.0 2.03 1.77 97 84 93
6500 39.1 34.0 20.7 1.89 1.64 90 78 96
7000 43.8 38.0 25.8 1.70 1.48 81 70 96
7575 51.0 44.3 32.0 1.59 1.39 76 66 108
At best cruising range and speed:
Malibu (340 HP engine)
RPM MPH Knots Total GPH MPG
3000 24.4 21.2 8.2 2.95
Mastercraft (350 HP engine)
RPM MPH Knots Total GPH MPG
3000 23.7 20.6 9.5 2.49
Yamaha (320 HP engines)
RPM MPH Knots Total GPH MPG
7000 27.5 23.9 7.8 3.50
SeaDoo
RPM MPH Knots Total GPH MPG
310 HP engines
5000 27.8 24.2 8.4 3.31
430 HP engines
6000 34.6 30.1 17.0 2.03
Keep in mind, these tests were conducted when the ballast tanks were not weighted, etc. so if you're running with full ballasts, the gas consumption will definitely increase.
The Yamaha engines are the most efficient based on the test results.
Regardless of gas consumption, get the boat that meets your family needs.