I was searching for a replacement for the ice cube trays that I had which were all silicone and getting one that was easy release of the cubes and not a struggle to get the cubes out.
I found the OXO ice cube trays to fit the need perfectly.  The top flap is silcone and seals nicely so the water does not spill when taking from the sink to freezer.  The bottom is a hard plastic and the cube come right out. [This review was collected as part of a promotion.]