I currently have a Harmon Kardon avr510 and am looking at buying the 80's for my mains. The problem is that they are 4 ohms althought my HK will run them eventually something is going to give. I need to know which is a good Amp to get for the 80's .I want separates with the HK being the pre/pro for a while. I am leaning towards a rotel 1080 for the front L/R and the 1075 bridged for the centre and a 1080 for the rears. Suggestions ?