Yes,all those KAW's were scary beasts,very 'nonlinear' throttle response.The 3cyl 750 was beyond scary for me,more like borderline lethal,so I chickened out with a 550.That one was bad enough.The trouble is that everything else seems dull&tame.There was no 3 cyl 900 BTW.Their nimble little Ninja 250 is quite potent and really fun to ride.Not that expensive either 3kB I think.
There was a reason that the 750 earned the nickname "widow maker" back in the day. I don't think going with a 550 was chickening out... just a sane choice.