I use the hard plastic moulds, having tried the soft ones. I took a chocolate course from Pascal Pouchon who taught me two things. Freeze in between for a minute or two. So, pour into the mould, pour out by suspending upside down in a bowl, scrape excess chocolate off into self-same bowl, freeze for a minute or two, fill, then use the excess chocolate to cover the bottoms. Then freeze again. The second thing helps with the bowl, a heat gun from the DIY store helps keep the chocolate above in the right temperature zone.