The way its implemented seems arbitrary. Doesnt run on checkouts if they are for a draft order payment, that doesnt make sense. Ok, so you might not run the line item scripts but shipping and payment scripts should still run.
Harford Road Liquors
They make a useful feature available to only their high-end costumers. Come on now like wtf...
Chase Street Accessories & Engraving
Only available to Shopify Plus, so not free at all. This is very disappointing, since it seems like a great feature!