Have been for a few months now.
I'm not 100% sure how great the cost savings are, although I'm sure I'm making some saving. For me the main advantage is I can load any length of roll (for some reason, I like to shoot in 18s or 20s).
Bulk loader (cheap off eBay), changing bag for putting the bulk roll into the loader, your long roll of your chosen emulsion, and some reloadable cassettes.
I wonder about cleanliness, but tbh I haven't noticed my negs from bulk load being any dirtier than the pre-loaded ones.
But there's plenty of people here with more experience than I.