The original generic magnetic fusion reactor paper was published in 1986 for deuterium-tritium reactors. This update describes what has changed in 30 years. Notably, the construction of ITER is providing important benchmark numbers for technologies and costs. In addition, we use a more conservative neutron wall flux and fluence. But, these cost-increasing factors are offset by greater optimism on the thermal-electric conversion efficiency and potential availability. In addition, today’s inflation and interest rates are low, leading to a cost of money well below that used in the original study. The main examples show the cost of electricity (COE) as a function of aspect ratio and neutron flux to the first wall. The dependence of the COE on availability, thermoelectric efficiency, electrical power output, and the present day’s low interest rates is also discussed. Interestingly, at fixed aspect ratio there is a shallow minimum in the COE at neutron flux of 2.5 MW/m2. The possibility of operating with only a small COE penalty at even lower wall loadings (to 1.0 MW/m2 at larger plant size) and the possible use of niobium-titanium coils are also investigated. It should be emphasized that the variation in the COEs is important rather than their absolute values.