The ImageWriter LQ GX driver, when used with GX-savvy applications, doesn't support the Best quality option. The selection is available, but it does not work. Engineering is aware of this problem and will release a new ImageWriter LQ GX driver in a future release of QuickDraw GX.
The current workarounds are to disable GX, use GX Helper, or use a non-GX-saavy application in order for the regular ImageWriter LQ print dialog to appear.
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