I have the 4.1 model. The sound is very good and they can easily fill a room. The only problem I have had, and this is such a minor problem, is the mini jack connection to the speakers. This is a pretty retarded design element for these speakers because sometimes the plug twists a little bit and it makes a bad connection. There is a hack for it out there somewhere, if you want to make a better connection.
Bottom line though is that I think the sound from these speakers is great. Get 'em.