Zu Speakers upgrade


I recently purchased a set Zu Omen Mk1 for $300.00. They are in excellent condition. Zu allows for upgrading to the new drivers. Does anyone have familiarity with this? Is it worth the $500.00 net charge. I am presently using a NAD C326 BEE to drive the Zu's. What is a good amplifier to drive these efficient speakers?
128x128coachpoconnor
Any of the First Watt amplifiers should be good. That is what Sean of Zu recommends and runs. Any low powered tube amplifiers like from Conrad Johnson will be killer.
I would say, Yes.
I own the Mk. 2 Omen Bookshelves and they were very good speakers. (I am selling them as I change my office system).
For $800, I think it will be a worthwhile investment. 
I used an Ayre AX-7e integrated, but really any decent amp out there should be good enough.
Bob