All the mathematical and computational problems concerning light scattering theory for spherical particles (Mie theory) are well studied and resolved. However, problems still remain to be tackled in the case of non-spherical particles. This requires systematic testing of corresponding numerical algorithms and codes. We consider different aspects of such checking: (i) reliability of the internal convergence test in view of our recent analytical and numerical investigations of some light scattering methods; (ii) efficiency of checking based on the reciprocity relation; (iii) new possibilities of comparison with other methods that are being opened by the developing WWW database of optical properties (DOP) of non-spherical particles. In particular, a general class of scatters (called 'weakly-Rayleight scatteres') to which the internal convergence test should be applied with great care is determined. The reciprocity relation is shown to be a useful test (under some conditions), specifically for absorbing scatteres. The DOP will contain original codes and well checked (benchmark) results as well as information on light scattering theory that can be helpful in research, applications and education.