Well, there are guys who will tell you that Cedar starts off sounding old, and I have to say that it does not age as dramatically as spruce.
But yes, any solid wood guitar will CHANGE with age. There are guys who will tell you that cedar gets played out after about 10 years. I don't buy that. My dad made my mom a guitar as a birth present when she was pregnant with me, which makes that guitar 31 years old, and it still sounds great. But that guitar has not been played much. Maybe if they get a lot of playing, they loose something - but I doubt it.
I'll tell you why I prefer spruce, though. Spruce has a more ballenced sound, with a much stronger fundimental than cedar, and it has a MUCH better dynamic range, particularly sitka. It really is odd how much you hear non-builder talk about this and that alternative top woods, but the vast majority of builders (who are in a much better possition to actually know the difference between the woods) have a strong preference for sitka spruce. The quality is still great (and should be great for a long time to come), and the sound is much better, at least to my ears.
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