I have a 95 with twin Yamaha 150 HPDI's and it is very adequate for all our purposes. Mostly 3 to four guys with usual fishing gear. We typically do not head out in adverse weather conditions and I have never had an issue with the power. I am conscious of the comfort of my passengers so I really do not run her hard. These motors seem to be very efficient as well. I am going to be installing a fuel management system this spring so I do not have any real numbers to substantiate my theory. Typical day of fluking, blue fishing, running about 20 - 25 miles we burn about 25 gallons. That is however a lot of staring and stopping, chasing blues or moving to a new drift. Probably the only way you would realize the difference if you switched form the 150's to 200HP. I really like the maneuverability with the twins as compared to the single on the Adventure. I couldn't imagine the difficulty at the dock with a single OB on this vessel. We mostly fish the ocean and am never are able to open it up anyway. 46 MPH, throttles pegged, in the bay only one time this summer, fast enough for me.
Of course if money is not a factor, get the 200's if the hull can take it, (weight factor) but you will not be dissapointed with the latter.