I tried the DL headphones once. To me, the difference was the noise canceling part. The QC-15's are far better, though the DL version works. I did find that if I hold the DL earcups closer to my ears, the difference was negligible but really, who wants a long flt where you have to do that? IMO, you already have the best so if canceling out the noise is important to you, stick with Bose.