[strat61caster]

Ok so I googled it and they are advertised as Pro-kit lowers 25 mm, Sportline lowers 35 mm, oddly the Pro-kit lists stiffer spring rates which leads me to believe the sportline relies on the bumpstops more heavily which is usually deemed undesirable from a handling and comfort perspective (although the OE setup utilizes the bumpstops frequently so it's not some sort of sin).

I believe that it is speculated that the Prokit is actually the same as the TRD lowering springs (rather that the TRD are rebranded Eibach Prokits), if I had to choose between the two I'd pick those, less drop = more suspension travel = more comfort. 1" is plenty for looks imo, others will likely disagree.

But if you wanna go low then the sportlines are the obvious choice. iirc Eibach designs each line to perform this way, sportlines as a more aggressive drop but ride harsher.

As mentioned by others there's more than a half dozen decent lowering springs for this car.