I don't know if I just don't have enough skill with them yet, but I have a challenging time making much from Carrara's metaballs. (I do do a good candle with dripping wax once.) Even when I do get something close to the shape I'm looking for, I have a hard time getting the edges nice and smooth no matter what I put the fidelity at. Maybe I just don't have enough experience with it though, which is very possible.