In what way is China socialist? It's a kleptocracy and an aggressively capitalist one at that.
Whether or not China is socialist or capitalist doesn't really matter: GP said "freer" economies have higher growth. Is China freer than Hong Kong or Singapore?
(BTW: China sure has a market economy, but OTOH it lacks multiple specifics of contemporary Western capitalist economies, e.g. it's not primarily driven by the financial markets, a significant portion of the workforce still works at state owned enterprises, much deeper planned macro economical development than in the West, ...)
Hong Kong and Singapore had an astounding growth of 2.9% and 3.9%, while socialist China had a miserable 7.7%? I don't get the impression you looked at the numbers at all, or did you?