For my main rig, the Thorens TD 160 Super/SME 3009 Series 2 Improved Tone Arm, I ran the Audio Technica AT440MLa for a fair while, but have recently changed that to the Ortofon OM series with a 20 type stylus (nude elliptical). I believe the Ortofon is a better match for the tone arm and preamp than the AT440MLa. The Cambridge Audio 651p preamp is known to be bright, and having the 440 running through that required an adjustment of loading using parallel resistive loading. Many records still sounded over bright on that combo. I do give the 440 high praise especially for its flawless tracking, and good bass response, but it is time to try something different. A channel imbalance was also evident with this cart, switching back to the Ortofon corrected this. A higher output was also achieved.
Previously when I ran the OM series cart on this rig, the 10 type stylus was used, and struggled with inner groove tracking on some Lps, (it was setup and aligned correctly). The 20 type stylus tracks much better, and I will consider upgrading to a Super OM cart and 30 type stylus in the future.