Using the new Beta 4.0 version, it would be a great help to be able to "Save" or "Save As" using 4:4:4 instead of 4:2:0 Chroma. For example, after working on a *.bmp image, and saving it, using the full 4:4:4 allows much more color accuracy if it's saved as a *.jpg file. Also, optimizing the "Huffman Table" would make for a more accurate image. At present, Chroma Subsampling seems to be fixed at 4:2:0 which doesn't give good color accuracy. Using the full 4:4:4 Chroma only increases file size by a slight amount.
Thanks.
See this URL for additional information: http://www.wikipedia.org/wiki/Chroma_subsampling