So I have noticed mine crashing too, and then vmware thinks its down, but its kind of up? This is with a new install too, and if I power off via esxi gui, and then unregister it and re register it, and remove the SATA host in the edit options, it seems fine…for a bit. I gave it 4 cpu, and 4gb memory.... still happened a few times before I gave up. This was all in one night :s.
Heeeey, this is related: https://forum.pfsense.org/index.php?topic=137628.15
TLDR: 2.4.1 fixes it.