  We present a discussion of the precision for the PHOTOS Monte Carlo
algorithm, with improved implementation of QED interference and multiple-photon
radiation. The main application of PHOTOS is the generation of QED radiative
corrections in decays of any resonances, simulated by a "host" Monte Carlo
generator. By careful comparisons automated with the help of the MC-TESTER tool
specially tailored for that purpose, we found that the precision of the current
version of PHOTOS is of 0.1% in the case of Z and W decays. In the general
case, the precision of PHOTOS was also improved, but this will not be
quantified here.
