My first several track events were on the stock suspension. There is value in seeing what the car is capable of in stock form before making any changes.
If the choice is between mods and track events, and you haven't driven your car on the track yet and have a lot of interest in doing so, then go with the track events. There is no substitute for driving experience -- the driver mod is by far the most potent one. There is enough to learn at the beginning that you can do so with pretty much any car. Modifications are not required in the beginning.
Hopefully, doing the track events will only delay the point at which you can change dampers. I also would go with nothing less than Koni Sports.
You might be surprised at how well the stock dampers work on the track. It'll probably depend greatly on the nature of the track. I've had my stock dampers dynoed and they do seem to be well matched to the spring rates at lower shaft speeds (the speeds that govern handling). The main problem with them is that they're underdamped at high shaft speeds, which is why you feel reverberations when going over sharp small bumps.
To be sure, the Koni Sport dampers will be an improvement on the track, but with stock springs, my experience is that the improvement is not the major one that one might expect. It takes some experience to really see the differences. Oddly enough, the smoother you are with the controls, the less you'll notice the limitations of the suspension (save for, e.g., understeer, which isn't primarily controlled by dampers).
If you haven't tracked your car before, then the stock setup is just fine -- just make sure you replace the brake fluid with good, high temp fluid (I like Castrol SRF myself), and make sure your pads have plenty left on them.
