I've worked on just about every type of outboard out there. Around here, numbers don't lie, and i'd have to agree. As far as being a good motor, the Yamaha four strokes are hard to beat. I'm a Mercury man at heart, but the Verados just don't do anything for me. Mercs used to renowned for their corrosion resistance, but now i see them crumble and fizzle like all the imports. The proprietary software on the Verados don't lend themselves to being a choice for independents like my self. There is an aftermarket software package available now, I looked around and noticed I have three verados in the 5 dry stacks I work in that aren't under warranty(they go back to the dealer for service). I work on over 100 Yamaha engines every year, the majority of them being four strokes, the majority of the work I do is regular maintenance. I have yet to find a F200/225 with the corroded oil pan issue, but I know they are out there, just not that plentiful around here. The most common thing I've found that blows up yamahas(and any other EFI engine) is a stuck thermostat(open) that allows the engine to run too cool, the computer compensates and runs the engien rich, gas gets by the rings and dilutes the oil to a water like consistancy. Thats what usually knocks the bearings out(that or water ingestion)I've mentioned my friends that have the harbor taxi that sold their F150's that had over 5000 hours on them(theri current engiens have over 4000). They've had issues with the engines(corrosion and lower units), but they are still running on a grady down in Fl. I like the Suzuki engines, but I've seen some severe corrosion on them personally, they have supposedly changed their alloy, we'll see in a couple of years how they hold up. I believe Suzuki has the best fuel system and one of the better lower units. The biggest disappointment with four strokes to me is Honda, they are way too heavy, way too big, too expensive, not that powerful per the rating, corroded horribly, I don't like the conversion, and parts are high.
When it comes down to it, i can't afford any of them, I'll stick to my old 2.4L 200 merc and my 88 special Johnrude. One thing I can say, is all motors fail in severe conditions, it matters if they are worth repairing or just throwing away.
