How you should does not matter cos the end product speaks for itself. Sometimes I shooot in P mode even. LOL. Most of the time I shoot in A-mode, and during some event I shoot in S-mode. Why so concerned? People talk down if you use other mode? Ask them to shop a better photo of the same one before talking down. If they produce one ok sure bow down to them, but ignore them if they cannot.
I will not shoot action with M mode! I cant even handle MF properly cos I wear specs and have astigmatism, so my eye focus ALSO have problem LOL. I trust the camera AF more hehehe.
Enjoy the process man!