Snapshot of PDF page for export to JPG has bugs
If you open those files in Acrobat, and use the snapshot feature, then "control-a" to select everything, you will see differences in each one. In each case, on the right side, the app selects more than it should be selecting. For example, the sample with inset and color has a small band of white on the right side that is included in the selection that should not be. This was a bug in Acrobat 9. I was hoping to find this problem fixed in this version, but it is not. I only discovered this recently, because I started adding background color to my pages that I was exporting to acrobat from Indesign, and when I exported them, I noticed the uncolored band on the right. It is not a problem with the margins (all .25 in), and the gutter is zero. These are single page exports from Indesign, not facing pages. I suppose the problem could have its origins in some bug in Indesign.
If no background color is included in the original page from Indesign, then this problem isn't noticeable unless you are looking at it very carefully. The problem still is there, but not obvious. I thought it might have something to do with the gutter, but I've changed it from .6 to zero and back with no change in this problem. The margins are all the same .25 on left, right, and top.