I'd pass most likely. Updated faction books is something I was expecting to see in the future as the game doesn't have much on the new faction GMCs characters in it and the new junctures. The older faction the older FS edition books are good enough to cover the older ones in most cases. Any faction books need to cover multiple ones so as not to take too long till they all get released or require you to have to lug a bunch of books around. 2 or 3 factions in a book would be a good number.
A huge problem with 1st edition s that a lot of players and GMs tended to avoid running games in certain juncture or using certain factions till a source book with that faction was released as very little was known about certain junctures and factions.
I also wasn't very happy with the editing of 2nd edition as a lot of well known mistakes got kept in and I don't like not having all the option 1st edition had with regards to character creation. If given achoice over playing 1st edition or 2nd edition I'd go with 1st
Originally the 1st edition game was to have meta-story that would advance each year. If something like that was done I might be tempted to back a book.
One book I would back would be one to cover the 1st edition stuff that doesn't have a 2nd edition equivalent and add some assorted stuff the way the old Golden Comeback book did.