Change host management IP addresses

I may have a need to change the IP addresses of my management interfaces on my ESXi 5.x hosts.   Unfortunately I thought it was a good idea to add all of them to Vcenter using their IP address, not hostname.    So I guess A) what is the best way to change their IP and keep them connected to vCenter and B) should I switch to DNS names in the future?  I kind of thought not having to depend on DNS resolution would be nice which is why I used IP, but I suppose I could use host files on my Vcenter for that.   

TIA.