Netgear EX7000 series questions

Hi all,

I was trying to find out what the differences are between 3 different models of the ex7000 are:

 EX7000-1AZNAS

EX7000-100NAS

EX7000-100PAS

  Cant seem to find any information that says whats different between the 3.

Also if this would be a good model for setting up as a range extender and then down the road as a access point.  I will be wanting to plug in a hard drive to this unit to use as a network storage device to access files between computers, phones, tablets, and TVs.  As well as hooking up 3 printers.  If you have any other suggestions please do say.

 Thank you in advance.