Can't compare with the 15s but I do like these little beauties. They are light and comfortable and although they are not completely sealing of your ears unlike other models they do a very good job. Don't expect that your surrounding noise will be dissapear completly (suppressing 90%) but you can really lower the volume and experience an almost silent trip. You definitly notice the difference when you have to take of your gear preparing for landing. The normal plane noise are quite disturbing then. You have to get used about the lightweight block (battery) but no show stopper.
Only downside is the cheap neoprene case for these expensive set.

Hope this helps. If you have any specific questions let me know.