medhorn, yer fono-stage has to have lotsa lo-noise gain to use a lo-output m/c. if it does, then i'd recommend a lo-output m/c vs a higher-output coil. many mfr's make the same cartridge w/different output specs, & i've never read about *any* of the hi-output wersions sounding better than their lo-output siblings.
if ewe don't wanna drop a bundle on a cartridge, & can handle a lo-output version, i'd try the ortofon mc25-fl - retails for $450, but always on special at the needle dr. for $225.
re: hi-mass arms, generally, m/c cartridges are heavier - so they need a heavier arm. if ya have a lite cartridge, then a lite arm is ok.
doug