Swaybars are a tuning tool is exactly right, if they are fitted too tight or not tight enough no matter how good the brochure looks they can have a severely adverse effect on the cars characteristics.
My coilovers also adjustable valving. The car's handling at the moment is very neutral, but the rear will still step out before it understeers (on neutral throttle). With the hp it has the car steps out anyway under throttle but it has a surprising amount of grip, easy to differentiate between a fast corner exit and being a peanut and just bagging the rears.
I also race superbikes, where suspension tuning is paramount to a fast lap time so I'm pretty well versed on how to play with it. My issue was to eliminate the wheel hop which I have done so happy days!