Hi all. This might be a really stupid question, but I won't know until you answer it. How would a pair of M&K surround 550 THX Select speakers (coupled with a decent sub >> MS309 or BK XLS200) fare as main front L/R speakers? Are they comparable to the M&K S85s? Would they be a downgrade from Mission 774s? They would be used with a Denon AVC-A11SR and DVD3800 (70% movies / 30% music). Thanks in advance.