I've moved my Maggie 1.5QRs through better and worse adapted rooms, without ever regretting them. I find that even in poor rooms you can get a small spot where imaging and sound really blossom, its just hard to enlarge the sweet spot. Even in a sub-optimal setup I think you have to spend twice as much to equal the sound of the Maggies. As for position advive, getting them AT LEAST 18 inches or if possible 2 feet from the back wall makes a huge difference. also angle them in slightly in a small roomand try and leave at least 6 or 8 feet between the speakers.
Good Luck.
Good Luck.