I love mine, best accessory 2nd to my Ultrex. she gets real light and skidish at WOT for a 18' boat, my best is 54.1mph GPS. Now I don't have the jackplate gauge but I go off the ruler on the jackplate. I run mine around 1 1/2'' on the ruler and when shes up and at wot I trim up until i get revs and then I jack it up to 2'' and she'll rev-out to 6,200rpm at wot