Hey man.
I have had V3s on two cars: my heavily modified '04 SVT Focus and on my lightly modified '04 Audi S4 wagon.
SVT experience: The KW V3s were the first significant change that I did with my Focus (spring 2004). They were great on the track. My recollection was that I wound up having a setup up that was relatively stiff on compression (front and rear) and comparatively soft on rebound (specifically thinking about the rear). It made for a bouncy ride around town, but we were trying to make the car a little more stable during hard braking out of a long straight into a specific high-speed sweeper at Pacific Raceways. Before we tilted that way (when it was more neutral), I tended to get a little looser than I'd like during braking. This is just my recollection from a few years ago, so YMMV. Nonetheless, the handling with the V3s was actually really great for track days. It was a little rough for on the street the way we had it set. During the first year into having the V3s, one of the shocks started to leak. KW replaced all of them on suspicion of a bad batch. That car added a supercharger, welded-in cage, heavy duty camber plates, all manner of extra fluid cooling, racing seats, etc. The V3s served me well throughout (and had a life-time warranty...until it found another home). Car was sold in spring 2012.
S4 Wagon: The V3s were really the only significant modification that I put on the wagon. Again, it was done almost as soon as I got the car in spring 2004. They were great, once we dialed in a little more stiffness (vs. default recommended starting place). They did a little of the oscillating waves over rolling surfaces at high speed. That stopped with more stiffness. This car never has gone to the track, so I never got to experience it in that setting. I took them off in 2012 and found that they had all started to leak or had completely failed. I sent them back to KW in SoCal and they rebuilt them. Only cost to me was the shipping to the refurb facility. I sold them when I got them back (fully retuned to factory "like new" condition) and switched back to the stock shocks (which had been sitting in my garage since 2004). I'm actually happier with the stock setup. It's less jarring. And for around town, I like it. The wagon still handles great. It's just more civilized over train tracks and such. It's a comparatively low-mileage car that I plan to have it till the wheels fall off.
As for me, I figure to just go with some mountune springs for the Fiesta and leave it at that. My objective is to have some fun at the track. My mountune mods should help with that, while limiting the $$$ thrown into the black hole of car modification.