Hi Ewen, thanks for your reply!  These don't follow proper formatting of addressing as well as failing to use the exisiting addr:unit tag.  While it may cause errors with some routing engines (i.e. not expecting to parse a '/' in the middle of an house number, etc.), I haven't tested it with the like of OSMAnd or even the website directly.  It is always best practice to use the tags that exist as practical as possible, and this falls in line with that.  As far as the number of them and my placing the notes, its easier to spot these errors in OSMAnd, and I will just take care of them myself.  They don't show up in the normal error catching methods as such, but are certainly in need of proper formatting for current and future routing engines to route correctly to provided address data.  As an American here in AUS, I can say prior to my arrival, I would not have been able to parse 5/25 Somewhere Street to mean 25 Somewhere Street, Unit 5.  Thanks again for your reply!

Brian