There is a output test for it here, but keep in mind that the specimen djozz tested was very green, so the numbers are quite a bit higher than it would be on a not very green specimen.
At 5A, which is the current i believe this LED is drawing on this setup, it produces approximately 1400 lumens at 18W, not bad, not terrible. For a SFT40 to produce the same intensity this LED is producing at 5A it must output 2650 lumens at 36W, which is right at its peak output. The heat generation would be enormous, and considering that the Yinding already didn’t like the titanium host (big hole on the shelf didn’t help), it would be even worse with the SFT40. Realistically speaking the SFT40 wouldn’t run that hot on the TS10, the stock cell wouldn’t provide that much current for it, so it would probably run at 7A, which is already 24W, and the intensity would go down 17% compared to the Yinding.
So, using the SFT40 on this light would result in a increase of 33% in heat generation and a decrease of 17% in intensity.
In almost any other situation where heat dissipation and current draw isn’t a problem, and you aren’t chasing that last candela, the SFT40 would be a better option.