It should be the same process - discover un-initialized array, allow you to set IP addresses and account names. I've never tried using the Navisphere tool for the VNX, but it probably will work. If you've already used it to setup the array and the array is running fine it should be OK.
Is there any difference ? 
What is difference between initialization of new VNX array by Navisphere and 
Unisphere ?