After researching Sony, RCA, and Sennheiser wireless headphones I settled on the Sennheiser RS-120's and I have no regrets. These are excellent headphones. I ended up buying them at GoogGuys. When I asked the associate if I could try them he connected them to a DVD player and they came to life. I walked all the way accross the store filled with electronics and heard no interference what-so-ever. I was nothing short of impressed and bought them right then and there.
Now that I have been using them for several weeks I am still amazed by them. I didn't know wireless headphones could be this good. There is no interference around my house. The 300ft range claim is about right. Maybe a bit conservative. I can mow my rental house lawn accross the street and even go next door and still get a good signal.
Sound quality is excellent. Bass is strong, mids are prominent, and highs are crisp. These phones work great for music, TV, and movies. I couldn't be happier with the sound. There is some spotty static in a couple places upstairs but it is practically inaudible when listening to something.
I don't know how long the batteries last because they have never run out. I have worn them for almost 10 hours straight and they were still going strong. I put them on the charger after each use and they have never shown any signs of a low battery.
That brings me to the charging system. It is simply superb. Unlike most other wireless phone charging systems this one is very simple. Just set the headphones on the metal "tube" that sticks out of the base and it charges. No messing around to get them just right so the contacts will contact (AKA Sony).
Build quality is very good. They are light weight, yet sturdy. The RS-120's are much sturdier than any of the other Sennheiser RS phones. They are very comfortable as well. I was worried that, due to their open air, on the ear design that they would get uncomfortable after wearing them for a few hours. I was proven wrong. They have never become uncomfortable.
I have read some reviews where people complain that the base turns off whenever it wants. It has an auto-off features so that it shuts off if it gets not signal for a few minutes. I see no problem with that and it has never bothered me since I'm usually listening to something when I'm wearing them. :)
I have the base connected to my home theater receiver to which I have a TV, DVD player, and my PC connected. The phones work well with all of those sources. Games, music, movies, TV, everything sounds great and I recommend these phones whole heartedly. You would be hard pressed to find a better deal in this price range.