The Abyzz are running like a top. We have never had a noise, vibration, or wear issue. I took one apart two weeks ago to see how it is holding up, and it looks like new. There was no scoring, wear, sediment, or calcification in the moving parts.
I have found that they overheat if run at full throttle. An alarm and warning code comes up on the controller. It isn't the pump that heats up, it's the remote power source. I believe this issue is a conflict of running the 50hz motors at 60hz. I was informed by the manufacturer (Venotec) that this should not be an issue, but I would wait for a 120v, 60hz native pump.
The other brushless DC pump we are using is 250 watts, made by another company. I took it apart at the same time as the Abyzz and found some mild pitting/corrosion on the motor's magnet. This is the part from China, all of the moving parts are premium materials made in the EU. If they change the motor, it is a best practice, but not yet. It delivers 5,500 GPH at 250w, compared to 6,500 GPH at 420w. The other benefit is it costs $1,000 instead of $2,000 and the power source runs a lot cooler 80˚F vs. 140˚F. You can't beat the Venotec Abyzz controller though.
I hear D-D Solutions will be distributing the Abyzz pump when it comes to North America. I assume they will offer a 120V, 60hz version at that point in time.