I think Suzuki and Yamaha four strokes are the best outboards on the market. Very reliable and still have the power. If you play around with the prop you should be able to get close to the same top end speed as the Mercury. You might be a tad slower but it's worth it to have a reliable motor and save on gas.

You asked if I've ever had trouble with the Suzuki's. I've had eight of them and had one powerhead blow(it was my own fault not the motors). I ran it while the overheat alarm was going off. I had sucked weeds into the impeller. I was in a tournament so I kept going so as not to get DQ'd. Suzuki fixed it no questions asked. I can say without a doubt that you will be 100% satisfied with the Suzuki.