The gel I've been using has the Vanga brand, but I don't have any reason to think it is better than Sterno. I just repeated my kitchen table test, this time measuring the weight of fuel. The gel was 10% faster, but only because it used 50% more fuel, so it is not more efficient. Also, this burner lasted about 15 minutes from full. I'm not sure that would be enough for two hot drinks and porridge that I would want over a single night/morning.

On the positive side, the gel didn't make the pan sooty. It did leave some residue in the burner, but not so as to be a problem for me.