The grafting of A. caput-medusae seedling is quite easy. The scion also will grow well and you can expect some flowers in 2nd year after the grafting.
On the other hand, own-rooted seedling is difficult.
Seedlings are crabby and stop growing if the condition was mismatched with them.
I sowed seeds in 5 pots on 28/08/2010 and kept in a wet-box without repotting.
It seems the time of the repotting because they have grown as large enough.