[konjin]

It's not really good enough: https://www.oscars.org/science-technology/sci-tech-projects/...

Mixing violets and greens makes the spectral curve closer to that of sunlight.

Again, without seeing it in person there is no way to know how much impact this has.

Using a parabolic reflector however is the only way to go since you will not get diffraction or blocking of wavelengths.

[andreareina]

Without going into the pdf report, the multiemitter doesn't look better than the blended phosphor.

[konjin]

No, you would need to pick better diodes, and wider variety of them. 3 greens and two violets + phosphorus at least.