My problem with people citing those metrics is that they are true for Russia itself while ignoring that a large reason for those improvements was colonialism done to the occupied regions. Industrialisation was another thing that improved those metrics but that was hardly unique to the USSR. Some of those regions may have had benefits but here in Estonia it was pretty much all around bad. After the occupation ended the quality of life here improved rapidly.
As far as examples for socialism I'd say the USSR was an all around failure but people still defend it and even Stalin who basically guaranteed it's failure as a socialist project. In the baltic region the word communism is basically poisoned because of the USSR.