Magneto-optic media provide an attractive method of achieving high density information storage. Two primary media characteristics have limited the practical implementation of magneto-optic technology: environmental data retention stability and high performance. In this paper, we present the dynamic performance, data retention stability, and environmental lifetime characteristics of a new high performance magneto-optic8media which has been demonstrated to achieve >50dB of. C/N for storage densities >4)(10 bits/inch with data rates up to 75 Mbit/sec. Coated on a plastic, pregrooved substrate, this high performance media has an expected lifetime of more than 8 years.