Ive been usig the xl1 16:9 mode and actully found it not to be too bad however there is a slight loss in quality because pixels are being streatched. The only other way I know to convert is what the BBC do which is crop or resize the image so its slightly streatched but not as much as the xl1 does. This way you get 16:9 with less quality lost and only abit of black at the sides that you would only notice if you had an underscan monitor.
Hope this helps you
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