APA citations are a pain. I went to a graduate school program that required APA format and it was painful to learn all the minutiae on the formatting. We used Diana Hacker's guide (which is like the Cliff's notes of APA/CMS/MLA formatting) but there was still quite a substantial section devoted to APA formatting.
Reference lists had hanging indents (which I missed on my first try of a reference list assignment). Each entry of the reference list had a very rigid format with tons of periods that separated all the fields. The worst part of the APA formatting was that it required listing 6 authors before you could move on to the "et al" shortcut (MLS lets you do that after 3). You would not believe how many telecommunications articles have 6 authors!!!!! It was very annoying to type out these names in their specific format! <lastname>, <first initial>., (that is period then a comma) and then you have to remember the last one gets & (not the word "and"). Very tedious!
The APA format is also inconsistent when it comes to capitalization of journal articles and books. Journal articles get all major words capitalized, books and others do not (they use sentence format). I don't see why they do this, it just makes formatting things more painful.
The worst part is that some online databases (that have the article I needed for free) do not contain all the information (journal volume number, issue) that the article was originally printed. I suppose that this is really the fault of the database, but the APA standard is pretty strict when it comes to including that information. I usually had to consult another database (which did not have the article for free, but had the complete citation) to complete the listing.
Articles that had DOIs saved me a lot of time. Articles that did not were really annoying.
Clearly I am not a huge fan of APA format, but I did it because that was the standard the department at my graduate school used.