I was recommended this stove base through Kyle, who was shown how to make it from Chris Girard. To be honest, I was pretty skeptical, judging the device as something that is useful, but not much better than the typical shovel blade. However, after using it on a 130 km ski traverse, it is worth all of its 37 g in saved fuel and hot water not spilt.
To make the pad, glue the bottom heat sheild of your stove to 5 mm foamy with shoe glue, cut out the circle and you are done (image attached of top, bottom and parts of the pad).
The problem with shovel blades is that they melt out, causing the stove to become unstable while transfering a lot of heat into melting snow around, but not in, your pot. The insulated base results in no noticable meltage of snow under the pad, implying that all heat is directed up, towards your pot (or the sky). This means that more of your fuel goes to melting water in your pot and the stability of stove base does not change with time. I don’t know how much fuel it saves, but 1.5L of boiled water takes about 33 g of fuel, so it almost justifies its existence if it saves one pot of water from falling over.
I highly recommend this nifty idea and now consider it part of my standard winter kit.