An amp like the Music Hall A25.2, at about 50 wpc, should easily drive these speakers, but the real question you should ask yourself is why would I want to listen to these speakers through any amp?
According to Zu, the
Omen and the
Essence, a higher priced model, share the same 10.3" wide-range driver, but have different tweeters. The Omen has what looks like a dome tweeter mounted in a wave guide fixture, and is blended with the wide-range driver with a 1st order high-pass filter at 18 kHz. The Essence has a ribbon tweeter with a 2nd order high-pass filter at 12 kHz. Because of the very high range for these tweeters, you might call them supertweeters, but they really go no higher than most other standard tweeters. Neither model uses a true crossover that contains a low-pass filter for the large driver. And that is the main problem.
I wasn't able to find a review of the Zu Omen, but I did find
this review about the Zu Essence. Because they share the same wide-range driver and have similar if not identical cabinets, some aspects of the review are relevant to the Omen.
Figure 5 on the measurements page shows the frequency response curve, and it is not at all smooth.
The Zu's midrange response shows that the so-called wide-range driver is in breakup at and above 2 kHz, and there is a large dip in the frequency response 2-6 kHz range. A driver in breakup sounds harsh and depending on the music, can lead to listener fatigue. You won't be able to hear the large dip, but its absence will affect your perception of treble presence. Good sounding speakers should have a flat frequency response across the entire midrange. These 10.3" drivers should be crossed over to a tweeter at about 1 kHz, certainly no higher than 1.5 kHz. Instead, Zu uses no low-pass filter to block these audible higher frequency problems, and chooses to call them wide-range drivers. They clearly are not.
Figure 2 shows some large cabinet resonances in the range of 300-500 Hz. You would likely hear that cabinet ringing as coloration of the midrange. They could probably be minimized or eliminated with better cabinet bracing.
At a similar price for the Zu Omens, there are many other speakers available that won't have these problems and will likely sound much better.