Thomas Sanlander did a review on the MM3 a while back, and he was very impressed as well, and was particularly impressed with the quality of the printer. You can find his review on YouTube.

Personally, it's a toss up between this and a Taz 5. On one hand, I prefer the Taz 5 simply for the praise it's gotten in the press lately, and Aleph Object's desire to continue to keep everything they do open source and libre. On the other hand, as much as the prints prove me wrong (and having built and designed printed printers myself) I just can't shake the negative notion of the printed components on the Taz 5. My mind keeps saying, for that cost, I'd like to see more metal components.

The MM3 has an amazing structure, the use of Openbuilds V-slot, especially the massive 20x60 profile on the X axis screams stability. I believe the deflection rate on that length of 20x60 is practically non-existent, far less than that of the standard 8-12mm linear rod typically used.

There's small things like the lack of a print cooler, or the lack of an LCD screen, cable carriers without buying an upgrade that turn me off on the MM3, but overall, both machines are great choices