Coilovers are useless for street cars. The majority are way oversprung and not only does this massively decrease ride comfort, it also actually decreases the grip of your car in a lot of street situations. With an overly stiff spring your suspension and hence your wheels lose the ability to follow the road surface where it is not racetrack-like flat. People spend thousands on coilovers then run a spring so stiff their fancy damper doesnt even get the opportunity to do anything useful.

I'd go for the Konis with a reasonable spring rate. They will be much better for the street than a cheap poorly damped coilover, even one with a lower than usual spring rate.