My order of "BCB Adventure Fire Dragon Solid Fuel (6 x 27gm Tablets)" came today. I tested them out.
Each tablet is packaged in small container with a peel-off foil lid. Size is about 2-7/8" x 1-3/4" x 1-1/8" (72 x 45 x 30 mm). The tablet itself is denatured ethanol in a wax-like gel substrate. It is labelled as fuel, but the instructions assume it is being used as a fire starter under charcoal or tiner. The instructions also state, "Can be used as a hand cleaner."
Because it melts after being lit, it must be contained within something if used as a fuel. I put it in a 3" diameter metal tin.
First, I tried heating 16 oz. (455 ml) of water using the Olicamp cup & G.A.K. stove. The tablet burned out after about 7.5 minutes. There were only a few bubbles at the bottom of the cup, but not even close to boiling. Then, I repeated the experiment with 8 oz. of water, and got very vigorous boiling after about 5.5 minutes. I suspect the optimum amount of water for one tablet would be about 10-12 oz.
So it's way better than Sterno. Due to the limited burn time, if nothing else, it's not competitive with the Trangia alcohol burner.
The tablet produced a very big yellow flame. There was a slight breeze outside, but there were frequent large flares of flames out from the side of the stove. Sterno and the Trangia produced much more focussed flames.
When the tablet was done, there was a thin layer of odorless white plastic residue at bottom of tin. It was pretty inoffensive, and I could peel or scrape most of it out with a screwdriver. There was a slight bit of sooting on the bottom of the cup, as might be expected from the yellow flame. In my experience, pure methanol or ethanol burns with a very clean blue flame, so maybe the soot was due to the gel.
I don't think I would ever use these if I knew in advance that I wanted to boil some water for tea or coffee; I would just bring the Trangia burner and a small fuel bottle of alcohol.
But I like the idea of these tablets as a backup - something to toss in a daypack just in case. They are compact and clean and odorless and leakproof, and the whole cook kit, complete with a few of these tablets, would fit in a 4" cube.