Handling and comfort are two different things to discuss.
My FK's are not uncomfortable, but they are a bit stiffer than stock, and the H&R Cup kit that i originally put on the car.
Handling and comfort are affected by a multitude of things.
Tire Sidewall: More meat usually means a bit more forgiving, plush of a ride.
Tire Width: more "hookup", better cornering without skidding, more "rubber on the road" to stick with.
Tire brand and shape: each brand trys to bring their idea of "ideal" to the table. Some have stiffer side walls, some have squarer sidewall/patch for tighter cornering, some have tread designs that are suited best for comfort, some sacrifice comfort and road noise for contact patch and utility.
Suspension height: Typically, it's believed that handling on MacPherson Style suspension becomes worse as it's lowered.
Shock Bound / Rebound rate: how fast the suspension acts to "correct" itself can determine how stiff or sloppy it rides.
Spring rate: Another factor determining stiff/sloppy ride quality.
Sway bars: fighting against newton's laws and trying to stop body roll, for a flatter turn, allowing more weight distributed on the tires properly, helping prevent under/oversteer depending on the application.
It's a fine mixture of what you want, that will determine the right suspension for you.
Ever see some jacka$$ in a riced out civic that looks like it's bouncing down the road? Most likely, it's running shortened springs on stock struts that are blown. they no longer retain the ability to correct the vehicle from bouncing everywhere.
Ever see a car going down the road, and when they go over a bump, the car seems to move very little compaired to yours? That's probably someone on a really stiff setup.
At any rate, It's up to your needs. What are you wanting, Vs. What are you willing to sacrifice.
FK's were designed to go fk'n low. they do just fine at near stock heights, but when you lower something substantially, the shock bound/rebound is also reduced, giving the suspension system less room to react. That coupled with improper control arm geometry (out of spec due to lowness) can make a car handle not as well. This however, to most daily drivable cars, is rather negligible, or you learn to live with it. It probably won't send you careening off a cliff because your car refuses to turn-
Now if you're concerned with taking the car to autocross, SCCA, or race it in any way, you'll want to tune the car properly. In this, a fully featured coil over with dampening adjustability would be best. You'd want to cornerweight the car so everything is distributed evenly weight wise, and properly setup sway bars to do the right thing.
What is most important to you?