I have a Sony E400, which is an aperture grille monitor. I love it. It is bright and has excellent resolution. It displays the full range of colors accurately, including blacks. The refresh rate is sufficient to play games without ghosting. The image isn't grainy, like on some CRTs.
I suppose it's all subjective, but the ONLY thing I could imagine being a problem with my monitor are the two grey lines--which don't bother me in the slightest. They aren't even noticeable in games. I only notice them when I am working on a light background. For example, on this page, I can see the lones on the light yellow and light grey parts of the screen, but I don't notice them unless I actually try to notice them.
Other people are different, and the lines just drive them batty. Other than the lines, I don't see any negative to the aperture grille, and there are a lot of positives.
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