I recently maxed out my Denon receiver by adding my 4th pair of speakers. I am looking at advice to add a speaker select system that would give me more control over what speakers are playing. FYI- This unit only powers 3 pairs of speakers in my living room, dining room, kitchen, den, and outside. (Not home theater) I would like to spend under $300 for it if possible, much less if a good quality unit can be had for less. So far I think I am going with the Niles SLV-4, but not sure if there are any others as good or better in my price range. What other units should I consider? Thanks in advance.