I'm not saying they're not accurate; I'm sure they are. I'm just saying that the red blob in the middle of the present is difficult to nail down to a specific location.
On the Paragon Maps maps, each location is indicated with a single white pixel, surrounded by black pixels (or for plaques, the exact opposite) so that there's no "hmm, I'm here, where's the [whatever]? Maybe I'm not standing right in the middle. Is it over here?..."
Keep in mind that on most of these maps, a single pixel is 10.3125 in-game feet. A 3x3 pixel area covers almost 93 square feet, which makes it difficult to tell, for example, whether a present is next to a building or on its roof a hundred feet in the air. That was my main problem with VidiotMaps--not that it wasn't accurate (though some of the markers were a bit off), but that once I got to the marker, I couldn't find what I was looking for because I couldn't really tell very well where the exact center of the marker is.
When I get home this afternoon, if I have time, I'll try putting together a map so that you can clearly see exactly what I'm talking about. You'll say, "Wow, that
is a lot easier to find!"