Edit: This shower speaker is still going strong after 10 months. After a great deal of use from my three roommates and myself, the batteries finally died (took about 6 months). When the batteries got low, sound quality got bad, cutting in and out of the music a little. Changing the batteries fixed the problem completely. The speaker has also survived a drop in the shower when we tried to hang it on a hook that wasn't strong enough to hold it up. Durable and well worth the money!
My boyfriend got this for me for my birthday. I wasn't really sure what to expect--I wanted something along these lines, but I wasn't sure how well it was going to work. It has exceeded all my expectations--the sound quality is actually decent for a speaker that hangs in your shower and receives a transmission through a radio(?) signal. I have used it in my house and in my dorm room (where cell phone signals and radio signals don't come through) and I can still get a great signal in the bathroom. The speaker stays in my bathroom all the time and water doesn't seem to faze it at all (although I wouldn't suggest dunking it or anything). I really like knowing my iPod is safe and sound while still enjoying my tunes in the shower! I haven't tried taking the speaker outside yet, but I'm sure it will do fine when I do.
Set-up takes less than five minutes. Take it out of the box, pop batteries in, plug in the mp3 player, and hang up the speaker. Done. The speaker has its own volume control, which is really nice, but unfortunately it does not have any song-changing function. I just set it up with a playlist of a few songs I know I want to hear--problem solved. The dock works wonderfully with my iPod classic and MacBook, using the same hookup as a set of headphones. The one thing that I really wish it had was a charger, but I suppose that's not practical if they're aiming to make it universal to all mp3 players. Other reviews complain about the short battery life of the speaker, but I haven't had a problem with it. All in all, I'm really happy with the product and I would definitely recommend it!