Nutanix has served us well over the last 8 or so years.
Have lots of customer who run it and would echo your same positive review.
Prism Central has definitely gotten better with the UI since the earlier days. I still prefer Prism Element in some cases, but overall it all works pretty well.
We use HYCU for backups and while I was really skeptical about it in the beginning, it is absolutely solid in a Nutanix environment. Overall we are happy with Nutanix.