I think you'll be very happy with this setup. I use the SM55's for fronts with the Series 600 set filling in the rest of the channels and like that. You may want to consider a subwoofer to fill out the low end though, like the Def Tech ProSub 1000.
Definitive Technology - ProSub 1000 Series Subwoofer System - 750 W RMS - Black
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