I read a few reviews to check if I'd be adding anything new, and decided to make a few comments;
they do hug to the ears quite heavily which can be a bit uncomfortable for extended use, but the plus side is they do block out a fair amount of ambient noise.
The issue I had was with a previous set of Sennheiser Wireless headphones, the RS120s where I had to keep retuning them and got terrible inteference at times. I was using them to listen to music and films on an iMac with loads of mobiles, pagers GPS devices nearby so maybe I was just asking too much. After only a few days I gave up and found out about Kleer technology which these use. At a Richer Sounds they thought the model up, the RS180 had Kleer and the RS160 didn't but that isn't correct (Even the Sennheiser site doesn't list the RS160 as Kleer when you search). The box clearly said it does, as does the manual and from owning a set I can testify that is the case. With Kleer you get zero interference and it's a technology that has a wider bandwidth than Bluetooth so can actually provide CD quality sound.
The range of thse is good as I can go downstairs and still hear them fine and live in a house with thick walls. I can find the limits of the range if I go into the kitchen though. Not an issue for me, but the RS180 has a longer range if you need it.
I really bought them to listen to films late at night but love them so much I find myself listening to music through them and being able to walk around and always have sounds.