Hi guys. I get conflicting opinions on the net about rms ratings of amps and subs. I can pick up a used mrpm850 alpine that will be 800w rms @ 2 ohms. my sub is a new type r 1243d dual 4 ohm that is rated at 600watts rms. can I use this amp if I set it up right. most smaller amps are more money and I don't want to miss out on it. but can I safely use it??? any help appreciated. thanks