I have to say, this topic caught my attention.
IMO, pure socialism (i will even say, utopian socialism, if that's what the op meant) is not a reliable economic (!) system, but not in a way that it may or may not be effective, but in a way that it may make people(with stable/good economical status) discontent because economic equality is not doable.
People need their properties and that is a fact that is not erasable; ranging from a teddybear to a 3-story mansion, a person will always have the need to... well, have stuff.
However, a society which preserves some elements of socialist economic system will only prosper (i.e reach economic stability and good life quality) if (in my opinion):
a) uneployment rate is low
b) -> gnp is at satisfying levels (i don't know if you'll understand this one)
c) employed people are productive (i will justify this with a fact: in my own country people with a 8-hour work day work 4 hours effectively ! + people retire very early, gaining the status of a retired person, thus receiving help from the health department. this causes a country to reach a state when there are less people working than retirees and children together. )
d) brain drain is reduced (countries invest in free education (at least in mine,but high education is paid), but if the person moves out after they received their (high) education, we can look at that investment as a loss, in terms of manpower and money)
These prerequisites, combined with increased personal liberties and provided welfare for those who need it, can lead to a much better system than pure socialism is.
However, these are all economy 101 things. Please, do correct me because i don't know if i've gone over my head or gone off the topic here. : )