This melter is really pretty and looks lovely, but it isn't the best design in practical terms. It's very large, and the wax platform quite high above the candle. This, in conjunction with the small opening and few small air holes right at the top mean that the candle can't melt the wax sufficiently - it's too far below the wax and doesn't receive enough oxygen to burn efficiently so there are always portions of wax which don't melt. The wax platform is also very shallow which makes removal a bit more difficult.
Gorgeous melter the birds are just beautiful