Fairlight-CMI

Sorry for the silly question but I am a series IIx owner. I am 
looking to consolidate some of my vintage equiptment and had some 
questions about the series III and MFX. 
 I have seen where the series III can act as a sampler and also 
record audio is this done all within the series III or does it have 
to be routed out to a external mixer then sent back to the series 
III? 
 What are the key differences between the MFX 2 and MFX 3 other than 
the obvious cost? 
 I am trying to aquire a true workstation something that I only need 
one piece of equiptment to do all of my preproduction. 

kevin kelley