Just a note that on KVM OpenBSD runs very slow in terms of disk access for some reason (it takes forever to even format the partitions).
Any BSD is in my opinion one of the most reliable operating system period and one of the most secure, and OpenBSD is no exception.
It does not have a fancy installer but is dead, simple and minimalist, it’s about efficiency, security and stability first.
Boot the OpenBSD ISO
Press I for install or A for auto install
I recommend I because the install fails straight away if no DHCP lease is detected (very common in many remote environments or datacenters of course).
So make sure you press I for normal install
Choose your hostname
Configure more options