a top and side of the fridge and freezer top. They do work well as they have double seals. The seals aren't magnetic (like some home refers) rather there are some magnets imbedded in the door and frame which help to keep the door closed - but not much. On a side door you are going to need a real latch anyway (buy a real stainless one from McMaster if you need one - the boat ones are junk). On a top lid you don't need a latch anyway (until you roll over).

Having said all that, I don't think you gain a heck of a lot in this case from the vacuum panels. The vacuum panels are extremely good, for all intents no heat passes through. However that is only in the center of the panel, at the edges there is heat conduction and on a door there are a lot of edges. The result is that though the center might be R50, the overall effective average for the door is way less and perhaps not a great deal better than something insulated with good foam.

My frig is about 7 cu ft I think, insulated on 4 sides with Glacier Bay vacuum panels (including the two doors) and on the remaining two sides with 6 - 10 inches of XPS foam. Once cold and if no one opens the refer every 10 minutes, the holdover in temperate conditions is about 36 hours - so the insulation does work!