The most successful set up I’ve seen for these speakers is done by Klaus himself.
He shared that these speakers like to “breathe” and getting them off the rear wall yields the best result. At least 3 feet, as I recall. I am consistently amazed at the amount of bass achieved when these speakers are nearly in the middle of the room. Klaus also strongly advocates nearfield listening. Equidistant between the speakers and listening position, then moving the listening position inward until you achieve the soundstage you’re looking for. It’s a lot of experimentation, but the results are well worth it.
Toe in is often minimal, as the dispersion of the beryllium tweeters is incredible.