Hi,
Nutanix as a solution is incredibly powerful - but fundamentally it's built more for the provision of high disk IO workloads (DB, VDI) than the typical server/storage replacement that I would wager(?) you're looking at. That said, they recognise the merits of the Education market and are starting to tweak some of their lower end platforms to edge towards a price point that competes with the VRTX. As one poster highlighted, the support, although fantastic, is expensive, and doesn't reduce in price linearly with the hardware discount you negotiate - to the point where it actually looks quite odd on any quote you'll recieve. You may also find that you are inherently paying for a number of Enterprise features that you are unlikely to use (replication and DR - doubles the price) etc.
At Stone we designed the Integrum from the ground up for Education, to deliver 95% of the feature set of Nutanix, but at a price point that makes both the support and the hardware competitive with any server/storage refresh. We've upgraded it over 2 generations and are looking at how we progress it further. We have a VSAN version and a Hyper-V version and I'd encourage anyone to at least give it a look as part of a procurement process. But yes, I am bias!
Best of luck with your refresh!
Chris