Although it's mostly worked to my personal advantage, I generally loathe the combined PTO plan that's the current style. It's somewhat understandable from an employer's perspective--time you're not working is time you're not working and they don't need to potentially police abuses of sick time--but I still don't like it. "Sorry kids. We can't take that family vacation this year because daddy caught that bad flu last Spring."

But a non-trivial number of people have historically abused dedicated sick time; there are even people cheerfully admitting to it on this thread.