The more standardized things are the easier it is to interpret and put them in context, especially with scratchy radio, very busy frequency, foreign accents, as such. I teach the standard way and they can do whatever later.
Most, but not all, of the charter, corporate and airline pilots seem most of the time to be pretty close to the book. Changing frequencies they'll often say "twenty three fifteen" instead of "one two tree point one five". Old military pilots seem more likely to use "tree, fife, niner". I don't know - to me it's easier to express myself to center if I'm doing it more or less by the book, especially if they are busy.
Once flew 61111 and found it easier to get across if said, "six one (pause) one one one". The rhythm seemed to avoid brain drops when trying to figure out how many ones were involved. When shortened it's one one one. Know a guy with a airplane with a tail number something like 123GG. On a Thanksgiving trip he called himself 3 gobble gobble and says he got humorous reactions from all but one controller who made him say it per the book.