I just got an Onkyo SR601 receiver and it will not support 4 ohm loads so I have to get a new pair of speakers. I am currently using Klipsch KG2s for mains and Energy Connoisseur C-1s for surrounds. What ever I get, the C-1s will probably become the mains. Which would be the better choice, the Polk R15s or the Infinity IL15s? $150 is my budget limit.