The top color will darken eventually when exposed to UV light... if you plan on keeping this one for some years. The satin finish is very thin, seems like a lot of work to stain it in the traditional way, which I think would involve stripping the finish first. I used gel stain on the back of my D-40 after finishing with tru-oil, and I liked the results. Gel stain can go on top of finish with just a light sanding. But a lot of work! Took a lot of coats of the gel stain to get the red I wanted. Then I had to go back over it with tru-oil. I don't think I'd attempt this on the top of a guitar, personally, and not on an otherwise great sounding Martin, without maybe practicing on a beater. I was fixing a very bad refin on my D-40 which is why I didn't mind trying it on that guitar.