I've put hundreds of hours on both the Yamaha and Merc 9.9s over the past 10 years and think they are both great motors. I personally would buy the Yamaha first over the Merc. for a couple of reasons, one, fewer mechanical problems, second, the Yamaha is lighter, dry weight on the Yamaha is about 95lbs. the Merc.(big foot) is about 130lbs. Just something to consider if you're going to be raising and lowering the kicker numerous times during the day. Good Fishing