The only thing I could find with a web search was a dealer spec for the current Moonbeam/VLMT. They recommended a cartridge weight of 4-10.5 grams, which implies that the VLMT has low-medium effective mass. That would be typical for a mid-market arm designed in the 1970's-80's, when lighter weight, more compliant cartridges were the norm.
I hope my guesswork is useful. If you're cartridge shopping, try to borrow one from someone, mount it up and run the resonance tracks on the HFN test record. That will give you a pretty good idea of whether you need to go lighter/softer or heavier/stiffer. The responses to this thread might be helpful in that vein:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1080220187&read&3&4&
I hope my guesswork is useful. If you're cartridge shopping, try to borrow one from someone, mount it up and run the resonance tracks on the HFN test record. That will give you a pretty good idea of whether you need to go lighter/softer or heavier/stiffer. The responses to this thread might be helpful in that vein:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1080220187&read&3&4&