If you're placing the M100s so close to the front wall, I recommend you get port plugs. It's anyone's call how many you might need. Maybe you'll need them for all ports. I have Audyssey XT 32 like you and when I placed my M100s within a foot of the front wall (just for shits and giggles), Audyssey could not compensate. It never had that problem with my M80v2. I had to plug all the ports and then Audyssey could deal with it.
I have my M100s almost one third the way into my room. That allows them to develop a deep, layered soundstage. I also have them a little more than 12 feet apart and the soundstage is so frickin' wide, it's like I don't have walls (I have 21 feet width). In fact what's happening is, they are designed to reflect sound off the side walls in a very deliberate and engineered fashion (see Axiom's discussion on the Family of Curves or my poem from around December 20th). All v4 speakers do that BTW.
My M5s in my living room do the same thing as the M100s. It's like I don't have a front window or side walls! The only reason I didn't suggest M5s for you is because you want LOUD and you want clean. The M5s can go loud and clean but you're an SPL hound so M100s for you.
Note that you will get soundstage depth with the M100 close to your front wall but it likely won't be as deep as moving them off the wall. The last thing you want to do BTW is to move them into the room, be blown away by the depth, only to have to move them back against the wall. You may not be able to live with your room after that.
