Had a yamaha 15hp 4 stroke that I bought as a re-seller, 23.7 mph, no wind, no current, 93°F, 81° dewpoint at the time of testing. Factory 9x10 prop, turning 5960 RPM. Little heavy but it runs almost identical to a 15hp 2 stroke, right down to the time-to-plane. I had a video at one point, might be on this site. BTW, that motor was mounted on a 1548 war eagle, on the transom (no lift no PT&T and no jack plate). Hull weight 353 lbs. Trolling motor weighs about 55 lbs. Battery 39 lbs. Me 200 lbs. 2 seats about 30 lbs roughly. Tackle box about 25 lbs. 2 rods 5 lbs. Wiring probably 10 lbs.
I was tickled with it. I guessed around 13 mpg at cruising RPM and speed with that boat. I did not keep it long enough to really do a measurable MPG test.
Someone on here did a review of the Suzuki EFI 20hp, I was not impressed with the review. I don't have a lot of experience with suzuki, other than dealers must be harder to find if/when you need them for warranty service. I get the call pretty often, coupe 3 times a week on average-looking for a service center for Suzuki.