Depending on what your upgrading your suspension for. Serious racing enthusiasts? looks? I wouldnt suggest spending alot for something your not gonna use its intended purpose for. But if I were to choose from tenzo or teins, would definatly go teins. Eibach, H&R, Skunks, are all good springs. Good meaning, there name has a reputation, so quality is most likely there. Your shocks may blow, but shocks dont blow due to poor quality made springs, it varies for all cars. Some people may have the same lowered height as another, but ones shocks might go bad sooner then the others.