I am going to be powering an M&K 150 system and an additional 2 4ohm M&K speakers for a 7.1 setup. I have made up my mind on the outlaw 950 pre/pro but I can't decide if I need the extra power of the 770. I think 300 watts per channel might be overkill. I am leaning toward the 7100 with 165w per channel into 4 ohms. My room is a weird L-shape. It is 27 feet in length but only 6 1/2 feet in width in the middle part of my seating area. My ceilings are very low at 6 1/2 and jut down even lower in certain areas. Thanks for the help in advance.