Quote from TheBoulder;891922:
the set on far right is probably the most affordable and best value for money at this point in time. It's only really worth investing in ep 10 armor if there's nothing else you'd rather invest in (weapons). My Fio will most likely be using a apoc helm/gloves/boot + everlasting top+btm mix, and my Lann will most likely do the reverse of that (After he gets his ep 10 swords of course, although I don't really know if it's worth switching to ep 10 if he's using +12 raiders twin swords).
Of course there's still a lot of work to be done... Orz
It might be, since Raider's is pretty bad aside from Crit.
+12 is 1000 Attack and 8 Speed over a +10.
At base, Infinity Twin Swords have an extra 1500 Attack and 13 Balance. Raider's gets 1 extra crit.
Taking into account the fact that you're probably only going to get a +10 Lv. 70: Infinity Twin Swords will have 500 Attack and 13 Balance. Raider's will have 8 Attack Speed and 1% Crit.
To my knowledge, Attack Speed isn't too useful on Lann. The question is if 1% Crit is worth 500 Attack/13 Balance. I'm guessing the answer is probably no.
You could probably sell the +12 for a sizeable amount after you get an Infinity Twin Sword though.