[rosska]

I have the Garmin 4208 and love it. In my opinion garmin makes the best unit for saltwater fishing and there new platform for the 500,4000 & 5000 series is as good as it gets right now. All of these units are designed to be a chartplotter and sonar so I would highly recommend adding the sonar as it will tell you depth, temp, and let you read the bottom while cruising. One of the coolest things I just did is wire my E-Tec directly to my unit. The garmin will give you the readout coming straight off of the outboards ECU which is more accurate than any other means. The unit will display MPG, GPH, Fuel Burned, Fuel remaining in the tank, Trim % & RPM's. I am not sure how your Optimax would need to be wired to do this but I am sure it can be done. Another thing I would recommend is buying the unit from somewhere local or only a site like http://www.boemarine.com/ where there is a person like Jim that handles his business. With advanced electronics you will have problems and you need someone there to take care of you when it happens.