Use CMY colorspace. Clean up the scratches and dust specks with PhotoShop. Save the images as TIFFs or bitmaps with NO digital compression. PhotoShop doesn't do anything noticable to the properly exposed images this way. I am happy with the results.
Colors are great, resolutiuon is great, sharpness is very good.
A pro lab would be hard-pressed to give you the same resolution and color rendition. Currently NO digital camera can compete with this resolution or quality.