I have a 1998 115, which I believe is essentially the same engine as you are looking at. It has over 1,100 hours on it and the only thing I've done to it is replace the exhaust cover gasket.
I don't have anything against the 2+2 design, but you need to understand how it works, otherwise you will swear that something is wrong with you engine.
As stated above the engine only runs on 2 cylinders at rpm's below 1800 or 2000. It runs perfectly on 2 cylinders and I have idled for hours w/o any problem whatsoever. When all 4 cylinders kick it it also runs perfectly and produces plenty of power.
In my opinion, the only issue is the transfer between 2 & 4 cylinders. If you quickly put the throttle down all 4 light up and you are off to the races. However, if you slowly open the throttle you will hit a spot where it can't decide if it should run on 2 or 4 cylinders and at that point it will cough and stumble. On my boat that is the point where the boat is just climbing on plane. I don't generally have any interest in boating at that speed so it isn't an issue for me. But, on occasion I boat with a friend who likes to run his boat at just the speed where my 2+2 is stumbling and coughing trying to make the transition (I think by my buddy does that on purpose LOL).
So bottom line is that if you will be trolling, or cruising you are good to go with a 2+2. If for some reason you need to run at that transition speed 2+2 could be a problem for you.
