Well, the one I used, Yamaha 4 stroke (I don't own one but a couple of my buds do) at least doesn't stink like a 2 stroke, and it does idle down pretty well, but yeah, they do vibrate like a lawnmower engine and they are loud, way louder than my 25 Yami (which I troll with, BTW, and with a bucket out back it will troll as slow as the 4 horse). So I pretty much decided on the 6 or 8 horse 2 cylinder 4 stroke Yami, if I every get into any money that is. The other things about the 4 horse Yami that I dislike is the location of the shift lever and tilt lock, way over on the wrong side of the motor, and the short handle. The 6/8 Yami has the shift on the handle and has the tilt lock right in front, a way better arrangement. And all I'll look at is a Yami, everything else is either crap, overpriced, or both. Anyway, my $.02