Has anyone tried Padico's "Modeling Cast" or porcelain slips?

Well, the way I understand it that is a casting slip, rather than a resin. That means you need plaster molds, just like with porcelain.
Most air dry slips are very sensitive to moisture and some can dissolve completely in water, so it is not very durable over time.
A slip gives you a hollow cast, so that is convenient. I know people who have used similar products to make prototypes for parts that are later cast in porcelain, with good results.

It is cheaper than resins, but it is also a completely different product, a different casting process and in the end, produces a very different kind of doll. Think of it more like a papier maché slip. It is very strong in its own way, but in a very different way from polyurethane.

Hope that helps.

 

Lavandula, did you actually try it? I would be interested to hear if you did.
I plan to since I want to create a very small edition of dolls and I love the look of painted paperclay (I love to paint it too!) I am also considering porcelain, but thought this would be a good way to see if I like this type of mold making without investing in a kiln. I was wondering about whether or not it was fragile too. I just received the advanced BJD book by Yoshida and it shows casting with modeling cast

 

I'm interested in the product as well, however not tried yet. I find that Padico has many interesting bjd items when I browsing hobbylinkjapan. I used to buy here too.