Thanks all for replies; I'm planning to do a test setting up another PFSense 2.5.2 in same VMWare environment. With same packages and same configurations (importing them). Then I uninistall packages like Snort and NtopNG, and I'll do upgrade to 2.6 version to verify the behavior.
As my actual PFSense manages 6 public IPs (set as Virtual IPs on WAN interface) it's not so quick "move" them from a PFSense to another one.