MM technology is an improvement. A big one. It's actually a technology change, whereas "XL" was a tightening of tolerances that Transparent gained by buying some additional specialized test equipment.
Just as an example - with previous versions of Transparent coupled with top-of-the-line Vandersteen speakers, there was a slight veiling of resolution. With MM Technology networks, the veil was lifted.
If you like the AQ "house sound," you probably won't like Transparent. If you like Transparent, you probably won't like AQ. I think I know why Elberoth2 likes the Harmonic Tech stuff - to me, it sounds very similar to AQ.