#1. I assume you get that buff in your buffbar and aren't required to wear anything special to get it?
#2. Does it allow you to go overcap, such as 3/6 casting for mages, 20HPR, etc
I can see FC1 as the most important one simply because mages can roll with a -1 weapon that has extra properties on it. Or make it alot easier on 4/6 chars!