There is just something addictive about the highs that come from the dual tweeters. Acute clarity. M60 is single tweeter, M80 is dual.
The dual tweeter is a necessity in its respective speakers for two reasons. The first is power handling. The second is spectral balance given the multiple woofers and mid-woofers. I proved out the second point myself on the M100. With the top tweeter blocked, the highs weren't as clear. On the M5 however, with its single tweeter, they are crystal because one tweeter is enough given one woofer and mid-woofer.
