It's worth it if you will get a lot of track time and won't be skipping your electric bill to pay for them, but good strut/spring combos are plenty good for a road car.

 

Main difference is that dedicated coilover systems usually use rather high (read: punishing) spring rates and are height adjustable. while spring and strut setups don't offer height adjustability, and usually are more tuned towards street driving with lower spring rates.

BTW, unless you are really interested in handling well at track and auto-x events, you really should consider what a coilover set will be getting you into. 5-7kg springs tend to be quite stiff, you'll feel everything on the road, 8-9kg springs are really stiff, questionable for street use. Will it be worth it to take that kind of daily punishment for a few haha's on the track?

For me, at least, YES!

 

Yup. The caveat is, non-adjustable systems are pretty much expected to be for street-driven cars, so they are usually not optimized for dedicated track use, although there certainly could be a set. Ergo, coilovers, which allow you to dictate the spring/damping rates for your purpose. Personally, I'd prefer good "road" setups over coilovers, but I don't run in competitive classes either.

 

Well said. I agree, there are many suspensions that are separate coil and strut combo's which are very track oriented, or rally oriented. But usually coilover systems tend to be track oriented. But even with them, the key words are spring rate and dampening.