Does anyone have experience with a heterogeneous blend of servers in a Hyper-V failover cluster? We have a cluster with blended generations of Proliants (DL360 G9s and DL360 G10s), and I'm considering introducing Dell servers into the mix due largely to availability and pricing. Is this a bad idea, and why?
You can do it and it will work. You will need to have processor compatibility option enabled to migrate VMs between hosts. If you buy the same Dell servers, I would recommend you to split them into 2 clusters. Speaking about shared storage, in theory you should be able S2D, but you can face issues. S2D shines in the supported configurations. https://docs.microsoft.com/en-us/azure-stack/hci/concepts/storage-spaces-direct-overview
As another alternative, you can use StarWind VSAN. https://www.starwindsoftware.com/starwind-virtual-san
Of course, the easiest option (in terms of configuration) would be to use SAN.