While it's ideal to have the room space around each speaker symmetrical in size, shape & and reflectivity, many (most?) of us don't have that luxury. It's worth shooting for though, within whatever practical constraints you have to deal with. I always start with the speakers and listening spot in an equilateral triangle, and frequently end with the listening spot back a little bit from that. Keep your front wall surface at least 3' from the rear of the Spatials - the sides are much less critical. Use a tape measure after you are zeroing in on an arrangement you can both live with and get the distance from the tweeters to your ears exactly equal (it's well worth the trouble). Good luck and happy listening!