Galactic charged cosmic rays (notably electrons, positrons, antiprotons and light antinuclei) are powerful probes of dark matter annihilation or decay, in particular for candidates heavier than a few MeV or tiny evaporating primordial black holes. Recent measurements by e.g. PAMELA, AMS-02 or Voyager on positrons and antiprotons already translate into constraints on several models over a large mass range. However, these constraints depend on galactic transport models, in particular the diffusive halo size, subject to theoretical and statistical uncertainties. We update the so-called MIN-MED-MAX benchmark transport parameters that yield generic minimal, median and maximal dark-matter produced fluxes; this reduces the uncertainties on fluxes by a factor of about 2 with respect to their former version. We also provide handy fitting formulae for the associated predicted secondary antiproton and positron background fluxes. Finally, for more refined analyses, we provide the full details of the model parameters and covariance matrix of uncertainties.