Signal-to-noise ratio (SNR) and thermal stability issues are addressed to evaluate synthetic ferrimagnetic media (SFM) for achieving areal densities >100 Gb/in2. Thermally stable SFM is obtained at Mrδ values as low as 0.15 memu/cm2, utilizing a higher magnetic anisotropy for the stabilization magnetic layer. The SNR relations for SFM are decided by the effective Mrδ and coercivity, similar to conventional media. The recording characteristics of a low Mrδ medium was compared with a higher Mrδ medium used for the 106-Gb/in2 demonstration. Lower medium noise and higher signal resolution of the lower Mrδ medium indicate an areal density extension to beyond ∼150 Gb/in2.