  In this paper we investigate the level of agreement between observations and
"new" Asymptotic Giant Branch (AGB) models, as produced by updating the
physical inputs adopted in previous stellar computations. One finds that the
new physics increases the predicted luminosity of Horizontal Branch (HB) and
AGB stellar structures by a similar amount, keeping unchanged the predictions
about the difference in luminosity between these two evolutionary phases. The
best fit of selected globular clusters appears rather satisfactory, disclosing
the relevance of the assumption on the mass of the Red Giant Branch (RGB)
progenitor in assessing the distance modulus of moderately metal rich clusters.
The still existing uncertainties related either to the input physics or to the
efficiency of some macroscopic mechanisms, like convection or microscopic
diffusion, are critically discussed, ruling out the occurrence of the so called
"breathing pulses" during the central He exhaustion, in agreement with earlier
suggestions.
