What's the cheapest way to cube an item from Rare?

So I know super cubes have a *slightly* higher chance of raising the potential tier of items, but I was wondering if it was worth using regular miris until unique then using supers from then on, or if it's actually cheaper to just go supers all the way?

I don't think anyone knows the real odds, so you're going to get subjective answers.

One way: use occult until you get epic, then wait for a double miracle time and use supers, hoping for a double raise.
Another way: wait for the Unique Potential scrolls (attendance event ending mid-august).