In this paper the asymptotic relative deficiency of the sample $q$-quantile with respect to kernel type estimators of the $q$-quantile is evaluated. The comparison is based on the mean square errors of the estimators. The result suggests a purely analytic measure of performance within the class of kernels. It is notable that a similar situation occurs when kernel estimators of a distribution function are studied.
"Relative Deficiency of Kernel Type Estimators of Quantiles." Ann. Statist. 12 (1) 261 - 268, March, 1984. https://doi.org/10.1214/aos/1176346405