They are not good, as evidenced by a new paper by Buggle and Nafziger (pdf):
This paper examines the long-run consequences of serfdom in the countries of the former Russian Empire. We combine novel data measuring the intensity of labor coercion on the district level in 1861 with several intermediate and present-day outcomes. Our results show that past serfdom goes along with lower economic well-being today. We apply an instrumental variable strategy that exploits the transfer of serfs on monastic lands in 1764 to establish a causal link between past serfdom and current economic development. Tracking the evolution of city populations throughout Soviet times corroborates the finding of persistent economic differences. Furthermore, our results suggest a political economy mechanisms linking higher historical economic inequality with worse public goods provision (roads and education), as well as lower urbanization and structural change towards factory production, as explanation for this persistence. We do not find differences in contemporaneous cultural attitudes and preferences.
The pointer is from Pseudoerasmus.