I have been using epoxy clay, I think its the same as aves in US. Quite troublesome since I have to add them parts by parts and let them dry. Been using super sculpey lately, I like how it is very easy to sculpt, but not as strong as epoxy clay when harden. Sometimes it came out brittle and crumble like cookie, maybe I didn't heat it properly, I heat it too much too fast and ugly bubbles surfaces. Still need much practice on it. For bulk or thick layer I recommend epoxy clay, its hardens within hour and much more durable.