I do have mahogany cups, but they're on my Grado RS1i headphones. If I'm using a driver from the Grado SR-80 in the walnut cups, I don't think it would be a very fair comparison. The RS1i is a better setup / headphone, but keep in mind, when going for something a further up the chain, normally the level of improvement is quite minimal. Sure, the RS1i is a beautiful headphone with great mahogany cups, I still wouldn't be disappointed with many of the SR-80 / SR-80i based Grados that I've heard in many variations. Remember, at the end of the day, it's the music that matters most.