The two jobs that would get the most benefit from this are BST and THF, especially THF for anything non-merit. (When they /WAR or /BST for claim purposes) It's more of a toy for PLD and not something to bring to group activities unless to show off.
I use this on thf when I don't have a subjob in salvage, and it is pretty nice. I find the killer effect procs fairly often and has actually saved me a few times. Definitely a nice shield for thf and bst.
From a Bst perspective not a bad shield. However being a Type 4 shield (Tower) it wont block very often and at 400k or so its a bit pricey.
The average Bst is gunna need to carry at a minimum, a Muse Tariqah (for Reward) and a Pallas Shield (for Pet Defense boost) anyway. So rather than paying 400k for an item you wouldnt use too often you're probably better off paying 8k in Imperial Standing and getting a Sentinel Shield instead (3str 1% Haste, Type 3 shield, lv50).
Tatami Shield looks cool though, and the Killer Effect will intimidate anyone wearing Crimson Gear.
The ultimate non end game shield for bst. nothing but plus stats and enhanced killer effects. I don't see any other job that would greatly benefit from this shield versus the pricetag on it.
