Hi Everyone, All the critical feedback on the various codes (and especially FEFF) to be quite valuable, especially since the main aim of FEFF Project is to develop improved, user-friendly theoretical tools for x-ray and related spectroscopies. In my view the main difference between FEFF and codes like GNXAS and EXCURVE and MXAN is that FEFF only does ab initio theoretical simulations, with a minimum of adjustable parameters. The others named above also do fits, so they are truly ab initio codes. On the other hand, FEFF requires auxilliary codes like IFEFFIT/ARTEMIS, WINXAS, EXAFSPAK, etc. to compare with experiment. Fitting can, of course, even make non-sensical theory fit experiments with enough parameters, so one cannot directly compare fitting codes with theoretical codes. Although we have been interested in MEE for a long time, and know that such excitations must exist (since S_0^2 is not unity!), we have not introduced them into FEFF for lack of a quantitative theory. The sudden approximation does not appear to be very accurate, for example, due to the importance of interference terms, especially near the onset of MEE. However, it may be possible that the quasi-boson model (discussed e.g. at XAFS13) can provide such a theory. J. Rehr