Dear Chris: The weak point on the SPU cartridges is that are not the best trackers out there, they are heavy and low compliance.
A test record is good for tell you how good ( on test ) is the cartridge but the important subject is that your cartridge can works and perform fine through your " real " LPs with any single problem due to poor tracking, if your SPU is doing well on that regard then you have nothing to worry about and feel free to enjoy it at top level!!!
Now, if you have trouble about ( I asume the cartridge/tonearm has the right set-up.) you can try a little higher VTF, a different tonearm and/or add the Audio Technica vacuum platter to your AS TT .
Regards and enjoy the music.
Raul.