One of the main advantages of a coilover setup compared to lowered springs on standard McPherson style struts is the ability to lower the car without loss of spring travel, which in a competition application is very important. In this context ya pretty well gets what ya pays for...

But for regular street use not so important unless you plan to regularly travel at speed on undulating roads where suspension travel (or lack thereof) may be an issue.
IMO it would be better to get some quality lower springs (eg Eibach) + adjustable inserts (eg Koni) than to buy cheap coilovers....there are plenty of examples of cars with this sort of setup doing very well in club level motorsport events.

And for the record, coilovers do not neccessarily give a harsher ride than standard... eg the DMS 40 (with the particular springs they came with...Kings for the record) I had in the MY06 STI when set at the softer end of the scale gave a much more comliant ride than the standard STI setup

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