teins are nice, if you can live with the sounds (w/ pillowball uppers).. personally i don't think i'm even close to using them at their potential... i'll be corner weighing the car soon though.
gc and koni's ride very nice, with a good amount of adjustability, although less than teins... great value though.
don't know what you mean by "the stock shocks... are already self-adjustable", they are non-adjustable.
i don't recommend gc+stock shocks... the springs are way too short for the stock shocks and you will end up blowing them. if you want to keep stock shocks just get some neuspeed, eibach, etc... lowering springs. the ride is sporty yet very comfortable.
really depends on what you want to do with the car... also keep in mind excessively lowering your car may screw with ATTS...
do a search for more info.
White98SH