I did some gate testing when I took it, and while I took it on a terrible character the legacy is very worthwhile.
I tested it against a shapeshifter's lower tier form, as it does fairly consistent damage.
No Preps, No Gates - 48 Damage per hit
Stone Skin/Iron Skin/Armor - 36 Damage per hit (25% damage reduction)
Gates/Stone Skin/Iron Skin/Armor - 28 Damage per hit (42% total damage reduction, an extra 22% from just preps)
This was with pretty mediocre armor. I think the legacy is pretty outstanding.
