We are just about to buy a used 22ft. 2008 tritoon with a Mercury 115 EFI. We took a test drive and were taken back by the MPH. Private lake, no swells, no real wind. WOT at 22? Three adults on board. No lifting strakes.The engine has 292 hrs. Could this be the problem? It is extremely clean and in what looks to be excellent condition. Hate to let it get away,but we can't deal with top MPH of 22. We want to cruise,pull tubes and fish. looks to be the standard black painted prop. I don't know the pitch. Just a three blade. We don't want to risk the purchase and stay at this speed. Any thoughts or suggestions would be helpful. Thank you