  Various formulations of the exact renormalization group can be compared in
the perturbative domain, in which we have reliable expressions for
regularization-independent (universal) quantities. We consider the
renormalization of the $\lambda\phi^4$ theory in three dimensions and make a
comparison between the sharp-cutoff regularization method and other more recent
methods. They all give good results, which only differ by small non-universal
terms.
