Recently got a pair of DJ1's, mainly for portable use. Never had Ultrasone's before and I was a bit sceptical about the treble which they're apparently notorious for. Only had the chance to give them a couple of hours listening time so far, but first impressions are quite good actually, I'm pleasantly surprised. The seal is good, bass is tight and punchy, treble is sparkly but not as fatiguing as I was afraid of. They look quite flimsy in many pictures in my opinion, but in reality they're very sturdy built, seems like they can take a lot of punishment. They are also easily driven by my cellphone alone. So far so good.