Having read several threads, it seems people are claiming the sways, the springs, and the shocks each on their own solve the bouncing problem some people have. Which is the best solution for this and how about understeer? Do I need to get new sways or new springs, or new shocks/coilovers to loose the understeer, or just one item enough?

 

Bounce is a product of not having enough dampening power in your struts, usually related to not enough rebound. Shorter wheelbase car's are also known to have "freeway hop" which get's intensified the stiffer a given suspension system is. The best fix would be to go with a coilovers system that has it's dampeners matched to their specific spring rate. The other solution would be to wait for the aftermarket to bring sport struts online. Koni, will be out with their sport strut this fall, they will likely be the first on to market.

Or you could try and mask the problem with progressive lowering springs like the eibachs. But that's a half measure and I wouldn't trade linear springs (which is what your car has now) for progressive springs on a high performance vehicle, NO WAY. If the normally agressive spring stiffness of the coilover systems is a bit much for you, wait for the Koni sports to come out, I guarantee they will solve any bounce issue's.