Danny, "LOMC" = "Low Output Moving Coil." In your case that would refer to a moving coil cartridge whose rated output under standard test conditions is low enough to require you to engage the "Phono MC" switch on the amp.
The Benz MC20E2-L, rated at 0.5 mv (millivolts) and the Denon DL-103, rated at 0.3 mv would certainly fall into that category. The DL-103 has a specified minimum load impedance of only 100 ohms, though. However, I would be concerned that its sonics might not be as good at that value as at higher values.
The Dynavector DV-10x5, rated at 2.5 mv, would almost certainly not fall into that category, and you would use it with the "Phono MC" switch disengaged, as if it were a moving magnet cartridge. I suspect that the same goes for the Denon DL-110, at 1.6 mv.
The Audio Technica AT-F3III is also a LOMC, with a rated output of 0.35 mv, and like the DL-103 is specified for a minimum load impedance of 100 ohms. Again, whether or not it would do as well at that value as at higher values would be a concern.
In general, excessively heavy loading (i.e., too low a load impedance value) will result in adverse sonic effects such as reductions in dynamics, transient impact, and resolution.
The Soundsmith option suggested by Fleib is well worth considering, as the cartridge repairs and stylus upgrades performed by Mr. Ledermann of Soundsmith are nothing short of magical in my experience and that of many others. The downside may be a significant wait time, though, so Fleib's suggestion of a low priced cartridge to be used temporarily is also a good one.
Regards,
-- Al
