[SRL]

For the MD, the different sound comes from several things:

* golden era bracing
* baked top
* lightweight carbon/Adi sandwich bridge plate
* metal bridge pines (3x the mass of plastic/bone/tusq)

I don't know if I'd characterise the MD sound as brighter than an average non-MD, but it's definitely more "modern" or "lush" or "pretty" — probably with more overtones vs. fundamental than a standard Martin.

The way I look at it is, from lush to dry tone, you've got MD, Standard, and Authentic. They all still sound like Martins and still have a big low end, but they give you some tone choices depending on what you want.

The biggest advantage about the MD series, though, is that the binding is wood and doesn't come off like Martin plastic binding. So that alone might be a good reason to choose an MD.

Edit: as far a s future value, who knows. Pick a guitar you like and play it while you still can.
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