I've shined up several Martin 15 series guitars with great success.
I think they look better than the factory full-gloss versions and certainly better than the satin versions. Certainly more natural. GHS Guitar Gloss, old t-shirts and patience will get you what you want. Don't listen to the "let it age naturally" purists. the shiny "patches" from natural wear look stupid and the satin finish picks up terrible sleeve noise. Good luck!