So then, how do you get two subs to produce great bass in your place? Experimentation is the answer: Since there are no guaranteed best spots when it comes to positioning multiple subwoofers, moving it around and listening over and over is really the only way to get the subs locked-in with your lair.
I also use this method. I have found that raising the front of my subs by about 1.5" (upward tilt) and toeing them about 20 degrees inward (toward the MLP) yielded much better results for me. When I ran Audyssey with this arrangement, the sub distance was much more closer (9.5' vs 12.5' before. Real distance is about 8.5') and my sub trim level ended up at 0 vs 2.5 before.I use the 1/4 placement along my front wall. I do notice a bit of a dead spot about 2/3 of the way to my back wall. My seating location is about 2-3 feet back from there and the bass level is good for me.