I think what you are saying here is that 2-73 may do S1R agonism better.
Yes A2-73 S1R agonism together with muscarinic modulation and who knows what that may tickle receptors just so.
I, as I am sure you, have searched high and low for clinical trial results based on tests focused on an S1R Agonist in humans. There is I believe only one small related trial in humans for neuropathic pain, which if I recall right was inconclusive but indicating further trials would be justified.
Hence the Anavex trials are really the first in humans and supported by a raft of preclinical work.
Don't think any of us is going to find the tell tale data we would like to better assess the chances of Anavex success.