
When there is a vertical scroll, it looks perfect, but when there is no scroll, the rightmost column ends 1 pixel shy of the control border, resulting in a thick ugly 2px gray line (column header-high), continuing at normal 1px width below the header region. I had to write a hack for this, but I feel like it is worth reporting here.
To reproduce, just open the sample application and open Grids/TreeListView QuickStarts/Column Widths page, and collapse elements until the vertical scrollbars disappear.