For the Paladins curious about this shield, this is the sum up:
Size 1 shield, so it gives you a base 22% damage blocked on a shield block.
Due to it's 31 DEF (32 on HQ) you get an additional 15,5% (16%) damage reduction on shield blocks.
So in reality you only get a 37~38% damage reduction upon a shield block. Yes, you do block up to 75% of the time with capped shield skill, however, keep in mind that you can cap out shield proc rate on a size 3 too, which natively starts out at a base of 50% damage reduction on a block.
So realistically, it's great for reducing damage if you're standing around, it's horrible as a shield for use in combat. Typical mage shield or for the stats for WS mods.
An interesting side step to Genbu's shield for RDM's. Ditching the evasion and 1% -pdt for increase def with vit and mnd thrown in. Could be ideal for Requiescat set up. Or it might be use to prop your door open on your MH when guest come threw.