Have a quick question. So, I bought this power amp on Amazon and received it today. Specs say 150w(RMS) 5 chan driven 8OHM and 200w(RMS) 5 chan driven 4OHM. The manufacturer on Amazon says Factor Electronics. I spoke to customer service and he sent me a manual that has it rated at 120w(RMS 5 chan driven and 180w(RMS) 5 CHAN DRIVEN. So I asked him after he sent me the manual why the lower specs. He then emailed me a cover with the amp on it that has the 150/200. I am aware that OSD Audio makes an identical amp, the xa 5180. How can I find out which amp I have? I don't have the means to test my amp to see. Any suggestions?