"MMRTG contains a total of 10.6 pounds (4.8 kilograms) of plutonium dioxide (including Pu-238) that initially provides approximately 2,000 watts of thermal power and 110 watts of electrical power when exposed to deep
space environments."[1]
Even if ~110 watts per ~4.8 kilograms is good for legs in agile situations, as opposed to wheels in a slow-and-steady rover, losing one in combat means you've just given the enemy a few kilos of radioactive material.
"MMRTG contains a total of 10.6 pounds (4.8 kilograms) of plutonium dioxide (including Pu-238) that initially provides approximately 2,000 watts of thermal power and 110 watts of electrical power when exposed to deep space environments."[1]
Even if ~110 watts per ~4.8 kilograms is good for legs in agile situations, as opposed to wheels in a slow-and-steady rover, losing one in combat means you've just given the enemy a few kilos of radioactive material.
[0]https://en.wikipedia.org/wiki/Snow_Crash#Rat_Things [1]http://mars.nasa.gov/msl/files/mep/MMRTG_FactSheet_update_10...