I have a Michigan Wheel Apollo XHS in a 19 pitch on my tin rig. I am able to turn it about 6200 rpm on my factory tach. I am looking to go at least a 1' or two bigger. Want to bring my rpm down some. Anybody have any experience with this prop and how it compares to say a 20 or 21 inch Tempest Plus. Boat is a 2012 Crestliner VT17 with a 2013 Merc 75 four stroke with a Simons tune to about a 115.