Were Eastern European State Socialisms really that bad?

There is always this claim going around that Eastern European State Socialisms were bad and there were many negative things.

It is always the same, political camps, atrocities, people robbed of even little property they had, shortages of stockings and proper medical care, and so on.

Was it really that bad? What are these claims based on? Are they all complete fabrications? I know that political camps did exist, it is a necessary step in fighting counterrevolution.