I had a pair of Ultrasone PRO 900 for a while, and I like them very much. I ended up returning them because I decided they were far too large for portable, but I liked them still. I ended up only getting to hear them with ~100 hours of burn-in, but I thought they were by far in a way the most involving headphones I had ever had. I still want to pic up another pair, now that I don't need portable.