What Bill said. I've got an all koa K-65 and I chose it over a W-65, an 855 and a 555 for it's unique crisp tones. It's like you can hear all 12 strings individually. Like the Taylor website says, the tone is kind of in between rosewood and mahogany and the koa top gives it an even more koa-like sound. Its unique beauty is a major bonus, but that wouldn't have been enough of a reason for me by itself.