Personally, I would be very carefull about making a decision based on the material used for the cartridge body. Sure, the material used affects the sound, everything does; but there are many more things to consider, especially in the $200-$400 range. Seems to me that beneficial use of exotic body material will probably be found in much more expensive cartridges.
The only low output MC that I would recommend, based on experience, is a used Benz Glider. Otherwise, I would stay away from inexpensive MC's altogethter; especially when you have the Shure VMR and Grados available. Since you are looking for a low output MC, I trust that you have a suitable high gain phono section in your pre; don't use it for a high output Grado, use the low gain setting or too much hum will result. Good luck and keep us posted.
The only low output MC that I would recommend, based on experience, is a used Benz Glider. Otherwise, I would stay away from inexpensive MC's altogethter; especially when you have the Shure VMR and Grados available. Since you are looking for a low output MC, I trust that you have a suitable high gain phono section in your pre; don't use it for a high output Grado, use the low gain setting or too much hum will result. Good luck and keep us posted.