The M15 Super is the first high-output pickup to come from Ortofon. Previous ones required either step-up transformers or a booster preamp, and it is only fairly recently that either kind of step-up device was available with high-enough quality to avoid a noticeable degradation of the sound. Early step-up transformers muddied the bass, and previously-available booster preamps added noise or hardness or both to the sound. Now that there are excellent transformers available from Ortofon and other sources, and at least one extraordinarily good booster preamp (the Mark Levinson, at an extraordinarily high price$170), Ortofon's latest and best pickup doesn't require the use of either.
The Genesis 500 ($650) is the baby brother of Monster Cable's top-of-the-line Genesis 1000 cartridge. It is almost identical in physical appearance, differing only in its use of green body trim (the 1000 sports red pinstripes). All of the functional differences appear to be in the stylus and cantilever. The cantilever of the 500 is a hollow sapphire rod tightly attached to an inner aluminum tube (the 1000 has a diamond-coated boron tube cantilever). Its stylus is a 6µm x 35µm line-contact (3µm x 60µm for the 1000). Monster claims a stylus life in excess of 600 hours for the Genesis 500, more than 1000 hours for its higher-priced sibling. 
