this is a difficult question as it depends on what springs etc (and how old your shocks are). If your shocks are over 5 years old I would advise to change them as they will fail quicker and they won't really have enough damping force to benefit from the springs ride/handling wise
eibach test springs using bilstein b2/4 o.e replacement shocks (they did use sachs advantage o.e spec until a few years back).