I am in the process of purchasing a 2000 18' flats boat with a 2000 Yamaha VX150 (complete with 2 year factory warranty). <br />This is a great engine, but I have an opportunity to swap it for a new 2002 Yamaha HPDI 150 for an additional $3000 installed.<br /><br />I am wondering if this steep price increase is worth it. The fuel economy is better with the HPDI I have been told, but I would like to know how much better it is. I would also like to know any more possible advantages or disadvantages of one motor over the other.