Argent: I have found the 5B-ST to do an excellent job handling the center and rear speakers. I need to qualify that statement, however, by telling you: 1) the Coincident rear speakers are 3-4 db more efficient than the other speakers, which means the effective power (at the speaker) is almost identical for both amps. (Bear in mind that each 3db increase in speaker efficiency reduces by half the amount of amplifier power needed.) 2) My listening room is not very large, so my speaker setup is essentially a "near field" listening environment. 3) I do not tend to listen at "wake up the neighborhood" levels (although I have a subwoofer, and the Vandy 3A Sig's go down to about 26-28 Hz). All of that said, the center speaker and rear speakers generally do not require as much power as the front speakers, assuming your main front speakers are full-range. Most rear surrounds do not go much below 65-70 hz, so the amp does not have to drive a lot of bass information. I would summarize by saying that unless you have really inefficient center/rear speakers, have a large listening room, and/or like to listen at ear-bleed volume levels, the 5B-ST will probably do an excellent job for you. At the very least, ask your dealer if you can borrow a 5B-ST for a weekend home demo. I think you will find the 5B-ST to be very satisfactory. I bought mine for $1800 new, with full warranty. I have also thought about selling the 5B-ST to buy the 6B-ST, but the 5B-ST provides ALL the power I need for surround sound, so it makes little sense to spend another $1000 or so to buy more amplifier than I need.