I sliced and measured the throw of an SST20 L2 BA 6500K I got from KD. I read people were having problems with solvent dedoming and killing the bond wires, similar to with the SST40, so I went straight for slicing. I have sliced a few SST40s and it’s worked well. The bond wires limit how close to the die you can slice the silicone, so I have been slicing very close to the die over most of the area while leaving the silicone thicker around the bond wires. I used the same method with the SST20, pictured below.

I put the emitter in an EE X6 head to measure the throw at 7m, powered by a constant current power supply.
At 5A I measured 105kcd.
At 4A, 92kcd.
A bit lower than the dedomed XPG2 S4 (new style) that I measured at 115kcd direct drive (probably around 4.5A) with a 30Q. Some of the difference is probably because the dedome is not perfect on the SST20. I think it will be a good choice for multi-emitter lights because of the lower Vf.

Edit: I misremembered the XPG2 throw number. I just measured it at 95kcd at 4.5A. So the SST20 is close in throw.