I have tried 3 different docks all by Altec Lansing. They are fine for small room and listening to music at reasonable levels. I use them in my office or for outdoor listening.
This version of the IM7 had a great sound but they stopped working.
http://reviews.cnet.com/portable-spe...-31398069.html A newer version of this system is available. At louder volumes it just got all muddy sounding.
The problem with dock systems is if you ever want to play loud music the sound suffers greatly. They aren't built for high volume unless you are investing a bit of dough. As you say, your friends Bose docks fill a room but these are pricey. Think about investing in surround sound computer speakers that accept other audio inputs. Several system have input ports for personal audio players. Not much costlier than a dock system. More bang for the buck.