If Xyrik is looking to understand the cons of such a system, Marx might not be the best place to look for them.
I like primary sources :-) And do you think there is a chance that Comrade Xyrik will join the cause of the glorious revolution of the proletariat?
How much money would it take to engineer biological immortality for at least half of the world's population, within 20 years, with 99% confidence?