The matrix bracing system has been carried over to the Nautilus line. The major improvements in the Nautilus series is the cabinent design and the tweeters. I have heard the N 801m 802, and 805 and was impressed with them all. However the original Maxtrix series are impressive in their own right. There is a big difference in price between the 2 series as you know so the best advice I could give is listen to both and decide for yourself if the improvements are worth the extra dough. Both lines have their benifits and whichever you choose you know you are getting a quality product. Good luck.