This may be a bit harsh, but I think OHMSS separates the men from the boys (or something similar). To appreciate Bond properly, one really has to read Fleming. The film version of OHMSS is the closest to the original source novel (even closer than From Russia With Love); to my mind, that make OHMSS the best.
But then there are people - even on official websites - who call themselves Bond fans, but who've never read a Fleming book.
As for Lazenby; I think his performance was shamefully underrated. And there are several myths surrounding him, the most damaging being that he was sacked because he was no good. Not true; he resigned and turned down the seven picture contract the producers offered him.