I don't know about the tonal subtleties. I'm not even sure what a "warm" sound is, but I suspect it usually just means a sound that the writer likes. What I do know is that the quality of Marca reeds seems to me to be more consistent than the Rico reeds I switched from. I almost never have to reject one completely.From reading that thread on SOTW, I get the impression that they don't deliver a very warm sound.
so maybe Marca is not for me?