50-54 (barring merits), it already sucks. Without Slugshot, you'd be gathering TP for a craptacular WS.
55-75, well it's just not all too great. You're losing out on a lot of DoT as RNG. As DoA alluded to with the level 75 comment, you just aren't going to be getting the level of haste required to make that set-up work.
RNG:75 MNK:75 WHM:75 BRD:75 BST:75 SAM:75 WAR:75 THF:75 BLM:75
DRG:72 SMN:63 DRK:55 NIN:49 PLD:42 RDM:41 DNC:37 SCH:37 BLU:37 COR:20 PUP:22
Woodworking:88 Cooking:60 Alchemy:60 Bone:60 Leather:60 Cloth:60 Smithing:60 Gold:54 Fishing:33