I think Cuba is a bit of an odd one considering its a relatively small island nation undergoing harsh sanctions and as such relies a lot on its domestic crops which are mainly sugar, can't say I'm an expert on the topic though. What I personally would like to see though is obesity rates in the USSR considering it had plentiful resources and was a very large nation comparable to the USA but I literally can't find any stats anywhere.

Even if you believe in the whole thing of everybody only being in it for themselves, wouldn't a Socialist system still be better as everyone is deciding on what to do so nobody is going to decide to give the other guy more than everyone else?