I've had 2, the first was mahog with a spruce top, I liked it so much that when an all koa came up for sale I bought it. I did a side by side and the spruce top was a little louder and a little crisper. I just liked the more mellower koa plus love the look! The ports are similar to the top side sound port in letting the player hear the uke "voice" better. Sold the spruce top quickly, like you said they don't come up for sale often. I'm a big fan of LoPrinzi ukes (and guitars), great quality builds and sound.