We used an Esbit on our trip.
Residue on pot, too. It can be washed off but you'll have to put the pot in one of the Poop bags until you get home cause residue is kinda greasy.
1 tablet boiled a liter of water, which is perfect for deydrated food. Threw a couple in at once for a minifire to warm hands.
It's very light and when you're done you can pretty much throw everything away. It's not very ecological but we had to fly to Cali and it was questionable if they would let us on the plane with any kind of stove. I didn't want to invest in a Whisperlite + fuel bottles if I might have to leave it behind or get qualified for a strip search.